Title of Invention

SUBSTITUTED DIPHENYL HETEROCYCLES USEFUL FOR TREATING HCV INFECTION

Abstract The present invention relates to substituted diphenyl heterocycle compounds and pharmaceutical compositions thereof that inhibit replication of HCV virus. The present invention also relates to the use of the compounds and/or compositions to inhibit HCV replication and/or proliferation and to treat or prevent HCV infections.
Full Text SUBSTITUTED DIPHENYL HETEROCYCLES USEFUL FOR
TREATING HCV INFECTION
1. CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims benefit under 35 U.S.C. § 119(e) to United States
Provisional Application Serial No. 60/350,107, riled November 2,2001 and United
States Provisional Application Serial No. 60/405,472, filed August 23,2002.
2. FIELD OF INVENTION
The present invention relates to substituted diphenyl heterocycles and
compositions thereof useful for treating or preventing Hepatitis C virus (HCV)
infections. In particular, the present invention relates to substituted diphenyl
isoxazole, pyrazole and oxadiazole compounds, compositions comprising the
compounds and the use of such compounds and compositions to inhibit HCV
replication and/or proliferation as a therapeutic approach towards the treatment and/or
prevention of HCV infections in humans and animals.
3. BACKGROUND OF THE INVENTION
Hepatitis C virus (HCV) infection is a global human health problem with
approximately 150,000 new reported cases each year in the United States alone. HCV
is a single stranded RNA virus, which is the etiological agent identified in most cases
of non-A, non-B post-transfusion and post-transplant hepatitis and is a common cause
of acute sporadic hepatitis (Choo et al., Science 244:359, 1989; Kuo et al., Science
244:362,1989; and Alter et al, in Current Perspective in Hepatology, p. 83, 1989). It
is estimated that more man 50% of patients infected with HCV become chronically
infected and 20% of those develop cirrhosis of the liver within 20 years (Davis et al,
New Engl. J. Med. 321:1501,1989; Alter et al., in Current Perspective in Hepatology,
p. 83,1989; Alter etal, New Engl. J. Med. 327:1899,1992; and Dienstag
Gastroenterology 85:430,1983). Moreover, the only therapy available for treatment
of HCV infection is interferon-a (INTRON® A, PEG-INTRON®A, Schering-Plough;
ROFERON-A®, PEGASys, Roche). Most patients are unresponsive, however, and
among the responders, there is a high recurrence rate within 6-12 months after
cessation of treatment (Liang et al, J. Med. Tirol. 40:69,1993). Ribavirin, a
guanosine analog with broad spectrum activity against many RNA and DNA viruses,
has been shown in clinical trials to be effective against chronic HCV infection when
used in combination with interferon-a (see, e.g., Poynard et al, Lancet 352:1426-
1432,1998; Reichard et al., Lancet 351:83-87,1998), and this combination therapy
has been recently approved (REBETRON, Schering-Plough; see also Fried et al.,
2002, N. Engl. J. Med. 347:975-982). However, the response rate is still at or below
50%. Therefore, additional compounds for treatment and prevention of HCV infection
are needed.
4. SUMMARY OF THE INVENTION
In one aspect, the present invention provides substituted diphenyl heterocycles
that are potent inhibitors of Hepatitis C virus ("HCV") replication and/or proliferation.
In one embodiment, the compounds are substituted diphenyl isoxazole, pyrazole
and/or oxadiazole compounds according to structural formula (I):
where Z is CH (isoxazoles, or pyrazoles) or N (oxadiazoles) and X and Y are each,
independently of one another, O and N, provided that: (i) X and Y are not bom O and
(ii) when X and Y are each N, then Z is CH. The "A" phenyl ring includes at least
one, and in many instances two, substituents positioned ortho to the point of
attachment (R2 and/or R6) and optionally from 1 to 4 additional substituents, which
may be the same or different Although the "A" ring may include a single ortho (R2 or
R6) substituent, compounds which include two ortho substituents (R2 and R6) are
particularly active and useful. It is preferable that at least one of the substituent groups
at positions R2 and/or R6 provide some steric bulk. For example, it is preferable that
the R2 and/or R6 substituent be larger than a fluoro group.
The nature of the R2 and/or R6 substituents, as well as the optional substituents
at positions R3, R4 and R5, can vary widely. As a consequence, the "A" phenyl ring
may be substituted with virtually any substituent groups, provided that at least one of
R2 or R6 is other than hydrogen. When the "A" phenyl ring includes more than one
substituent, the substituents may be the same or different. Typical substituent groups
useful for substituting the "A" ring include, but are not limited to, branched, straight-
chain or cyclic alkyls, mono- or polycyclic aryls, branched, straight-chain or cyclic
heteroalkyls, mono- or polycyclic heteroaryls, halos, branched, straight-chain or cyclic
haloalkyls, hydroxyls, oxos, thioxos, branched, straight-chain or cyclic alkoxys,
branched, straight-chain or cyclic haloalkoxys, trifluoromethoxys, mono- or polycyclic
aryloxys, mono- or polycyclic heteroaryloxys, ethers, alcohols, sulfides, tbioethers,
sulfanyls (thiols), imines, azos, azides, amines (primary, secondary and tertiary),
nitriles (any isomer), cyanates (any isomer), thiocyanates (any isomer), nitrosos,
nitros, diazos, sulfoxides, sulfonyls, sulfonic acids, sulfamides, sulfonamides, sulfamic
esters, aldehydes, ketones, carboxylic acids, esters, amides, amidines, formadines,
amino acids, acetylenes, carbamates, lactones, lactams, glucosides, gluconurides,
sulfones, ketals, acetals, thioketals, oximes, oxamic acids, oxamic esters, etc., and
combinations of these groups.
These substituent groups may be further substituted at one or more available
carbon or heteroatoms with the same or different additional substituents, which may be
selected from the substituents described above. Any reactive functionalities in the
groups used to substituted the "A" phenyl ring may be masked with a protecting group
or a progroup, as is well-known in the art.
The substituent groups may be attached directly to the phenyl ring, or they may
be spaced away from the ring by way of a linker. The nature of the linker can vary
widely, and can include virtually any combination of atoms or groups useful for
spacing one molecular moiety from another. For example, the linker may be an
acyclic hydrocarbon bridge (e.g, a saturated or unsaturated alkyleno such as methano,
ethano, etheno, propano, prop[l]eno, butano, but[l]eno, but[2]eno, buta[13]dieno, and
the like), a monocyclic or polycyclic hydrocarbon bridge (e.g., [l,2]benzeno,
[2,3]naphthaleno, and the like), a simple acyclic heteroatomic or heteroalkyldiyl
bridge (e.g., -O-, -S-, -S-O-, -NH-, -PH-, -C(O)-, -C(O)NH-, -S(O)-, -S(O)2-, -
S(O)NH-, -S(O)2NH-, -O-CH2-, -CH2-O-CH2-, -O-CH=CH-CH2-, and the like), a
monocyclic or polycyclic heteroaryl bridge (e.g., [3,4]furano, pyridino, thiopheno,
piperidino, piperazino, pyrizidino, pyrrolidino, and the like) or combinations of such
bridges. In one embodiment, the "A" ring is substituted at both R2 and R6 with the
same or different halo, alkyl, substituted alkyl, alkoxy, substituted alkoxy, methoxy,
haloalkyl, trifluoromethyl, 5-6 membered cycloheteroalkyl or substituted 5-6
membered cycloheteroalkyl group.
The "C" ring is substituted at the meta position with a group of the formula
-NR11 C(O)R12, where R1' is hydrogen or lower alkyl and R12 is monohalomethyl or
dihalomethyl. The "C" ring may optionally include from 1 to 4 additional substituents
(R8, R9, R10 and/or R13), which may be the same or different As for the "A" phenyl
ring, the nature of the optional R8, R9, R10 and R13 substituents can vary broadly.
Groups useful for substituting the "C" phenyl ring are the same as those described for
the "A" phenyl ring, supra. In one embodiment, the "C" ring does not include
optional substituents, such that R8, R9, R10 and R13 are each hydrogen.
As will be recognized by skilled artisans, the actual electron distribution or
double bonding pattern of the "B" ring will depend upon the identities of substituents
X and Y. As illustrated, structural formula (I) is specifically intended to include at
least the following six structures:
In another aspect, the invention provides starting and intermediate compounds
useful for synthesizing the compounds of the invention. Representative starting and
intermediate compounds useful for synthesizing isoxazole and pyrazole compounds of
the invention include compounds 201,203,205,207,209, 223,225,227,229,231,
245, 247,248a, 248b, 249,257 and 259 as depicted in FIGS. 1-7. Representative
starting and intermediate compounds useful for synthesizing oxadiazole compounds of
the invention include compounds 265,267,269,271,285,287 and 289 as depicted in
FIGS. 1-7.
In one embodiment, the intermediates are compounds according to structural
formula (II):
wherein R15 is NO2 or NHR, where R is hydrogen, lower alkyl or a protecting group
and X, Y, Z, R2, R3, R4, R5, R6, R8, R9, R10 and R13 are as previously defined for
structural formula (I) and subject to the same provisos. Like the compounds of
structural formula (I), in the compounds of structural formula (II) the double bonding
pattern will depend upon the identities of substituents X and Y.
In another aspect, the invention provides methods of making the substituted
diphcnyl heterocycle compounds of structural formula (I) or (II). Specific exemplary
embodiments of the methods are illustrated in FIGS. 1-7. In one embodiment, the
method for synthesizing compounds according to structural formula (I) comprises
optionally alkylating a compound according to structural formula (II) in which R15 is
NHR with an alkylating agent (e.g., R11-halide) followed by optional deprotection and
acylation with an acylating agent of the formula LG-C(O)-R12, where "LG" represents
a leaving group or an activating group and R12 is as previously defined in connection
with the compounds of formula (I).
In another aspect, the present invention provides compositions comprising the
compounds of the invention. The compositions generally comprise a substituted
diphenyl isoxazole, pyrazole or oxadiazole of the invention, or a salt, hydrate, solvate,
N-oxide or prodrug thereof and a suitable excipient, carrier or diluent. The
composition may be formulated for veterinary uses or for use in humans.
The compounds of the invention are potent inhibitors of HCV replication
and/or proliferation. Accordingly, in still another aspect, the present invention
provides methods of inhibiting HCV replication and/or proliferation, comprising
contacting a Hepatitis C virion with an amount of a compound or composition of the
invention effective to inhibit its replication or proliferation. The methods may be
practiced either in vitro or in vivo, and may be used as a therapeutic approach towards
the treatment and/or prevention of HCV infections.
In a final aspect, the present invention provides methods of treating and/or
preventing HCV infections. The methods generally involve administering to a subject
that has an HCV infection or that is at risk of developing an HCV infection an amount
of a compound or composition of the invention effective to treat or prevent the HCV
infection. The method may be practiced in animals in veterinary contexts or in
humans.
5. BRIEF DESCRIPTION OF THE FIGURES
FIGS. 1-7 provide exemplary synthetic schemes for synthesizing the
compounds of the invention.
i
6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
6.1 Definitions
As used herein, the following terms are intended to have the following
meanings:
"Alkyl," by itself or as part of another subsn'tuent, refers to a saturated or
unsaturated, branched, straight-chain or cyclic monovalent hydrocarbon radical
derived by the removal of one hydrogen atom from a single carbon atom of a parent
alkane, alkene or alkyne. Typical alkyl groups include, but are not limited to, methyl;
ethyls such as ethanyl, ethenyl, ethynyl; propyls such as propan-1-yl, propan-2-yl,
cyclopropan-1-yl, prop-1-en-l-yl, prop-l-en-2-yl, prop-2-en-l-yl (allyl),
cycloprop-1-en-l-yl; cycloprop-2-en-l-yl, prop-1-yn-l-yl, prop-2-yn-l-yl, etc.; butyls
such as butan-1-yl, butan-2-yl, 2-mcthyl-propan-l-yl, 2-methyl-propan-2-yl,
cyclobutan-1-yl, but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl, but-2-en-1-yl,
but-2-en-2-yl, buta-l,3-dien-1-yl, buta-l,3-dien-2-yl, cyclobut-1-en-1-yl,
cyclobut-1-en-3-yl, cyclobuta-l,3-dien-1-yl, but-1-yn-1-yl, but-1-yn-3-yl,
but-3-yn-1-yl, etc; and the like.
The term "alkyl" is specifically intended to include groups having any degree
or level of saturation, i.e., groups having exclusively single carbon-carbon bonds,
groups having one or more double carbon-carbon bonds, groups having one or more
triple carbon-carbon bonds and groups having mixtures of single, double and triple
carbon-carbon bonds. Where a specific level of saturation is intended, the expressions
"alkanyl," "alkenyl," and "alkynyl are used. Preferably, an alkyl group comprises
from 1 to IS carbon atoms (C1-C15 alkyl), more preferably from 1 tolO carbon atoms
(C1-C10 alkyl) and even more preferably from 1 to 6 carbon atoms (C1-C6 alkyl or
lower alkyl).
"Alkanvl." by itself or as part of another substituent, refers to a saturated
branched, straight-chain or cyclic alkyl radical derived by the removal of one
hydrogen atom from a single carbon atom of a parent alkane. Typical alkanyl groups
include, but are not limited to, methanyi; ethanyl; propanyls such as propan-1-yl,
propan-2-yl (isopropyl), cyclopropan-1-yl, etc.; butanyls such as butan-1-yl,
butan-2-yl (sec-butyl), 2-methyl-propan-1-yl (isobutyl), 2-methyl-propan-2-yl
(t-butyl), cyclobutan-1-yl, etc.; and the like.
"Alkenvl." by itself or as part of another substituent, refers to an unsaturated
branched, straight-chain or cyclic alkyl radical having at least one carbon-carbon
double bond derived by the removal of one hydrogen atom from a single carbon atom
of a parent alkene. The group may be in either the cis or trans conformation about the
double bond(s). Typical alkenyl groups include, but are not limited to, ethenyl;
propenyls such as prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl (allyl),
prop-2-en-2-yl, cycloprop-1-en-1-yl; cycloprop-2-en-1-yl; butenyls such as
but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl, but-2-en-1-yl, but-2-en-1-yl,
but-2-en-2-yl, buta-1,3-dien-1-yl, buta-l,3-dien-2-yl, cyclobut-1-en-1-yl,
cyclobut-1-en-3-yl, cyclobuta-l,3-dien-1-yl, etc.; and the like.
"Alkvnvl." by itself or as part of another substituent refers to an unsaturated
branched, straight-chain or cyclic alkyl radical having at least one carbon-carbon triple
bond derived by the removal of one hydrogen atom from a single carbon atom of a
parent alkyne. Typical alkynyl groups include, but are not limited to, ethynyl;
propynyls such as prop-1-yn-1-yl, prop-2-yn-1-yl, etc.; butynyls such as but-1-yn-1-yl,
but-1-yn-3-yl, but-3-yn-1-yl, etc; and the like.
"Alkvldivl" by itself or as part of another substituent refers to a saturated or
unsaturated, branched, straight-chain or cyclic divalent hydrocarbon group derived by
the removal of one hydrogen atom from each of two different carbon atoms of a parent
alkane, alkene or alkyne, or by the removal of two hydrogen atoms from a single
carbon atom of a parent alkane, alkene or alkyne. The two monovalent radical centers
or each valency of the divalent radical center can form bonds with the same or
different atoms. Typical alkyldiyl groups include, but are not limited to, methandiyl;
ethyldiyls such as ethan-l,1-diyl, ethan-l,2-diyl, ethen-1,1-diyl, ethen-l,2-diyl;
propyldiyls such as propan-l,1-diyl, propan-1,2-diyl, propan-2,2-diyl, propan-l,3-diyl,
cyclopropan-1,1-diyl, cyclopropan-l,2-diyl, prop-1-en-1,1-diyl, prop-1-en-l,2-diyl,
prop-2-en-l,2-diyl, prop-1-en-l,3-diyl, cycloprop-1-en-l,2-diyl,
cycloprop-2-en-l,2-diyl, cycloprop-2-en-1,1-diyl, prop-1-yn-l,3-diyl, etc.; butyldiyls
such as, butan-1,1-diyl, butan-l,2-diyi, butan-l,3-diyl, butan-l,4-diyl, butan-2,2-diyl,
2-methyl-propan-1,1-diyl, 2-methyl-propan-l,2-diyl, cyclobutan-1,1-diyl;
cyclobutan-l,2-diyl, cyclobutan-l,3-diyl, but-1-en-1,1-diyl, but-1-cn-l,2-diyl,
but-1-en-l,3-diyl, but-1-en-l,4-diyl, 2-methyl-prop-1-en-1,1-diyl,
2-methanylidene-propan-1,1-diyl, buta-l,3-dien-1,1-diyl, buta-l,3-dien-l,2-diyl,
buta-l,3-dien-l,3-diyl, buta-l,3-dien-l,4-diyl, cyclobut-1-en-l,2-diyl,
cyclobut-1-en-l,3-diyl, cyclobut-2-en-1,2-diyl, cyclobuta-1,3-dien-1,2-diyl,
cyclobuta-l,3-dien-l,3-diyl, but-1-yn-l,3-diyl, but-1-yn-l,4-diyl,
buta-l,3-diyn-l,4-diyl, etc.; and the like. Where specific levels of saturation are
intended, the nomenclature alkanyldiyl, alkenyldiyl and/or alkynyldiyl is used. Where
it is specifically intended that the two valencies are on the same carbon atom, the
nomenclature "alkylidene" is used. In preferred embodiments, the alkyldiyl group
comprises from 1 to 6 carbon atoms (C1-C6 alkyldiyl). Also preferred are saturated
acyclic alkanyldiyl groups in which the radical centers are at the terminal carbons, e.g.,
methandiyl (mcthano); ethan-l,2-diyl (ethano); propan-l,3-diyl (propano);
butan-l,4-diyl (butano); and the like (also referred to as alkylenos, defined infra).
"Alkvleno." by itself or as part of another substituent, refers to a straight-chain
saturated or unsaturated alkyldiyl group having two terminal monovalent radical
centers derived by the removal of one hydrogen atom from each of the two terminal
carbon atoms of straight-chain parent alkane, alkene or alkyne. The locant of a double
bond or triple bond, if present, in a particular alkyleno is indicated in square brackets.
Typical alkyleno groups include, but are not limited to, methano; ethylenos such as
ethano, etheno, ethyno; propylenos such as propano, prop[l]eno, propa[l,2]dieno,
prop[l]yno, etc.; butylenos such as butano, but[l]eno, but[2]eno, buta[l,3]dieno,
but[l]yno, but[2]yno, buta[l,3]diyno, etc.; and the like. Where specific levels of
saturation are intended, the nomenclature alkano, alkeno and/or alkyno is used. In
preferred embodiments, the alkyleno group is (C1-C6) or (C1-C3) alkyleno. Also
preferred are straight-chain saturated alkano groups, e.g., methano, ethano, propano,
butano, and the like.
"Alkoxy," by itself or as part of another substituent, refers to a radical of the
formula -OR, where R is an alkyl or cycloalkyl group as defined herein.
Representative examples alkoxy groups include, but are not limited to, methoxy,
ethoxy, propoxy, isopropoxy, butoxy, tert-butoxy, cyclopropyloxy, cyclopentyloxy,
cyclohexyloxy and the like.
"Alkoxvcarbonyl" by itself or as part of another substituent, refers to a radical
of the formula -C(O)-alkoxy, where alkoxy is as defined herein.
"Alkvlthio," by itself or as part of another substituent, refers to a radical of the
formula -SR, where R is an alkyl or cycloalkyl group as defined herein.
Representative examples of Alkylthio groups include, but are not limited to,
methylthio, ethylthio, propylthio, isopropylthio, butylthio tert-butylthio,
cyclopropylthio, cyclopentylthio, cyclohexylthio, and the like.
"Aryl." by itself or as part of another substituent, refers to a monovalent
aromatic hydrocarbon group derived by the removal of one hydrogen atom from a
single carbon atom of a parent aromatic ring system, as defined herein. Typical aryl
groups include, but are not limited to, groups derived from aceanthrylene,
acenaphthylene, acephenantbrylene, anthracene, azulene, benzene, chrysene, coronene,
fluoranthene, fluorene, hexacene, hexaphene, hexalene, as-indacene, s-indacene,
indane, indene, naphthalene, octacene, octaphene, octalene, ovalene, penta-2,4-dicne,
pentacene, pentalene, pentaphene, perylcne, phenalene, phenanthrenc, picene,
pleiadene, pyrene, pyranthrene, rubicene, triphenylene, trinaphthalene and the like.
Preferably, an aryl group comprises from 6 to 20 carbon atoms (C6-C20 aryl), more
preferably from 6 to 15 carbon atoms (C6-C15 aryl) and even more preferably from 6 to
10 carbon atoms (C6-C10 aryl).
"Arylalkyl," by itself or as part of another substituent, refers to an acyclic alkyl
group in which one of the hydrogen atoms bonded to a carbon atom, typically a
terminal or sp3 carbon atom, is replaced with an aryl group as, as defined herein.
Typical arylalkyl groups include, but are not limited to, benzyl, 2-phenylethan-1-yl,
2-phenylethen-1-yl, naphthylmethyl, 2-naphthylethan-1-yl, 2-naphthylcthcn-1-yl,
naphthobenzyl, 2-naphthophenylethan-1-yl and the like. Where specific alkyl moieties
are intended, the nomenclature arylalkanyl, arylalkenyl and/or arylalkynyl is used.
Preferably, an arylalkyl group is (C6-C30) arylalkyl, e.g., the alkanyl, alkenyl or
alkynyl moiety of the arylalkyl group is (C1-C10) alkyl and the aryl moiety is ((C6-C20)
aryl, more preferably, an arylalkyl group is (C6-C20) arylalkyl, eg., the alkanyl,
alkenyl or alkynyl moiety of the arylalkyl group is (C1-C8) alkyl and the aryl moiety is
(C6-C12) aryl, and even more preferably, an arylalkyl group is (C6-C15) arylalkyl, e.g.,
the alkanyl, alkenyl or alkynyl moiety of the arylalkyl group is (C1-C5) alkyl and the
aryl moiety is (C6-C10) aryl.
"Aryloxy," by itself or as part of another substituent, refers to a radical of the
formula -O-aryl, where aryl is as defined herein.
"Arvialkvloxv. by itself or as part of another substituent, refers to a radical of
the formula -O-arylalkyl, where arylalkyl is as defined herein.
"Arvioxvcarbonvl," by itself or as part of another substituent, refers to a radical
of the formula -C(O)-O-aryl, where aryl is as defined herein.
"Carbamovl." by itself or as part of another substituent, refers to a radical of
the formula -C(O)NR'R", where R' and R" are each, independently of one another,
selected from the group consisting of hydrogen, alkyl and cycloalkyl as defined herein,
or alternatively, R' and R", taken together with the nitrogen atom to which they are
bonded, form a 5-, 6- or 7-membered cycloheteroalkyl ring as defined herein, which
may optionally include from 1 to 4 of the same or different additional heteroatoms
selected from the group consisting of O, S and N.
"Compounds pf the invention" refers to compounds encompassed by the
various descriptions and structural formulae disclosed herein. The compounds of the
invention may be identified by either their chemical structure and/or chemical name.
When the chemical structure and chemical name conflict, the chemical structure is
determinative of the identity of the compound. The compounds of the invention may
contain one or more chiral centers and/or double bonds and therefore may exist as
stereoisomers, such as double-bond isomers (i.e., geometric isomcrs), retainers,
enantiomers or diastereomers. Accordingly, when stereochemistry at chiral centers is
not specified, the chemical structures depicted herein encompass all possible
configurations at those chiral centers including the stereoisomerically pure form (e.g.,
geometrically pure, enantiomerically pure or diastereomerically pure) and
enantiomeric and stereoisomeric mixtures. Enantiomeric and stereoisomeric mixtures
can be resolved into their component enantiomers or stereoisomers using separation
techniques or chiral synthesis techniques well known to the skilled artisan. The
compounds of the invention may also exist in several tautomeric forms including the
enol form* the keto form and mixtures thereof. Accordingly, the chemical structures
depicted herein encompass all possible tautomeric forms of the illustrated compounds.
The compounds of the invention may also include isotopically labeled compounds
where one or more atoms have an atomic mass different from the atomic mass
conventionally found in nature. Examples of isotopes that may be incorporated into
the compounds of the invention include, but are not limited to, 2H, 3H, 11C, 13C, 14C,
15N, 180,170,31P, 32P, 35S, 18F and 36CL Compounds of the invention may exist in
unsolvated forms as well as solvated forms, including hydrated forms and as N-oxides.
In general, the hydrated, solvated and N-oxide forms are within the scope of the
present invention. Certain compounds of the present invention may exist in multiple
crystalline or amorphous forms. In general, all physical forms are equivalent for the
uses contemplated by the present invention and are intended to be within the scope of
the present invention.
"Cycloalkyl." by itself or as part of another substituent, refers to a saturated or
unsaturated cyclic alkyl radical, as defined herein. Where a specific level of saturation
is intended, the nomenclature "cycloalkanyl" or "cycloalkenyl" is used. Typical
cycloalkyl groups include, but are not limited to, groups derived from cyclopropane,
cyclobutane, cyclopentane, cyclohexane, and the like. Preferably, the cycloalkyl
group comprises from 3 to 10 ring atoms (C3-C10 cycloalkyl) and more preferably
from 3 to 7 ring atoms (C3-C7 cycloalkyl).
"Cvcloheteroalkyl," by itself or as part of another substituent, refers to a
saturated or unsaturated cyclic alkyl radical in which one or more carbon atoms (and
optionally any associated hydrogen atoms) are independently replaced with the same
or different heteroatom. Typical heteroatoms to replace the carbon atom(s) include,
but are not limited to, N, P, O, S, Si, etc. Where a specific level of saturation is
intended, the nomenclature "cycloheteroalkanyl" or "cycloheteroalkenyl" is used.
Typical cycloheteroalkyl groups include, but are not limited to, groups derived from
epoxides, azirines, thiiranes, imidazolidine, morpholine, piperazine, piperidine,
pyrazolidine, pyrrolidone, quinuclidine, and the like. Preferably, the cycloheteroalkyl
group comprises from 3 to 10 ring atoms (3-10 membered cycloheteroalkyl) and more
preferably from 5 to 7 ring atoms (5-7 membered cycloheteroalkyl).
A cycloheteroalkyl group may be substituted at a heteroatom, for example, a
nitrogen atom, with a lower alkyl group. As specific examples, N-methyl-
imidazolidinyl, N-mcthyl-morpholinyl, N-methyl-piperazinyl, N-methyl-piperidinyl,
N-methyl-pyrazolidinyl and N-methyl-pyrrolidinyl are included within the definition
of "cycloheteroalkyl." A cycloheteralkyl group may be attached to the remainder of
the molecule via a ring carbon atom or a ring heteroatom.
"Dialkylamino" or "Monoalkylamino," by themselves or as part of other
substituents, refer to radicals of the formula -NRR and -NHR, respectively, where
each R is independently selected from the group consisting of alkyl and cycloalkyl, as
defined herein. Representative examples of dialkylamino groups include, but are not
limited to, dimethylamino, methylethylamino, di-(l-methylethyl)amino,
(cyclohexyl)(methyl)amino, (cyclohexyl)(ethyl)amino, (cyclohexyl)(propyl)amino and
the like. Representative examples of monalkylamino groups include, but are not
limited to, methylamino, ethylamino, propylamino, isopropylaxnino, cyclohexylamino,
and the like.
"Halogen" or "Halo." by themselves or as part of another substituent, refer to a
fluoro, chloro, bromo and/or iodo radical.
"Haloalkyl," by itself or as part of another substituent, refers to an alkyl group
as defined herein in which one or more of the hydrogen atoms is replaced with a halo
group. The term "haloalkyl" is specifically meant to include monohaloalkyls,
dihaloalkyls, trihaloalkyls, etc. up to perhaloalkyls. The halo groups substituting a
haloalkyl can be the same, or they can be different. For example, the expression
"(C1-C2) haloalkyl" includes 1-fluoromethyl, 1-fluoro-2-chloroethyl, difluoromethyl,
trifluoromethyl, 1-fluorocthyl, 1,1-difluoroethyl, 1,2-difluoroethyl,
1,1,1-trifluoroethyl, perfluoroethyl, etc.
"Haloalkyloxy," by itself or as part of another substituent, refers to a group of
the formula -O-haloakyl, where haloalkyl is as defined herein.
"Heteroalkyl," Heteroalkanyl" "Heteroalkenyl" "Heteroalkanyl,"
"Heteroalkyldiyl" and "Heteroalkyleno" by themselves or as part of other
substituents, refer to alkyl, alkanyl alkenyl, alkynyl, alkyldiyl and alkyleno groups,
respectively, in which one or more of the carbon atoms (and optionally any associated
hydrogen atoms), are each, independently of one another, replaced with the same or
different heteroatoms or heteroatomic groups. Typical heteroatoms or heteroatomic
groups which can replace the carbon atoms include, but are not limited to, 0, S, N, Si,
-NH-, -S(O)-, -S(O)2-, -S(O)NH-, -S(O)2NH- and the like and combinations thereof.
The heteroatoms or heteroatomic groups may be placed at any interior position of the
alkyl, alkenyl or alkynyl groups. Examples of such heteroalkyl, heteroalkanyl,
heteroalkenyl and/or heteroalkynyl groups include -CH2-CH2-0-CH3,
-CH2-CH2-NH-CH3, -CH2-CH2-N(CH3)-CH3, -CH2-S-CH2,-CH3,
-CH2-CH2-S(O)-CH3, -CH2-CH2-S(O)2-CH3, -CH=CH-0-CH3, -CH2-CH=N-O-CH3,
and -CH2-CH2-O-C=CH. For heteroalkyldiyl and heteroalkyleno groups, the
heteratom or heteratomic group can also occupy either or both chain termini. For such
groups, no orientation of the group is implied.
"Heteroaryl" by itself or as part of another substituent, refers to a monovalent
heteroaromatic radical derived by the removal of one hydrogen atom from a single
atom of a parent heteroaromatic ring systems, as defined herein. Typical heteroaryl
groups include, but are not limited to, groups derived from acridine, (b-carboline,
chromane, chromene, cinnoline, furan, imidazole, indazole, indole, indoline,
indolizine, isobenzofuran, isochromene, isoindole, isoindoline, isoquinoline,
isothiazole, isoxazole, naphthyridine, oxadiazole, oxazole, perimidine, phenanthridine,
phenanthroline, phenazine, phthalazane, pteridine, purine, pyran, pyrazinc, pyrazole,
pyridazine, pyridine, pyrimidine, pyrrole, pyrrolizine, quinazoline, quinolme,
quinolizine, quinoxaline, tetrazolc, thiadiazole, thiazole, thiophene, triazole, xanthene,
and the like. Preferably, the heteroaryl group comprises from 5 to 20 ring atoms (5-20
membered heteroaryl), more preferably from 5 to 10 ring atoms (5-10 membered
heteroaryl). Preferred heteroaryl groups are those derived from furan, thiophene,
pyrrole, benzothiophene, benzofuran, benzimidazole, indole, pyridine, pyrazole,
quinoline, imidazole, oxazole, isoxazole and pyrazine.
"Heteroarylalkyl" by itself or as part of another substituent refers to an acyclic
alkyl group in which one of the hydrogen atoms bonded to a carbon atom, typically a
terminal or sp3 carbon atom, is replaced with a heteroaryl group. Where specific alkyl
moieties are intended, the nomenclature heteroarylalkanyl, heteroarylakenyl and/or
heteroarylalkynyl is used, hi preferred embodiments, the hcteroarylalkyl group is a
6-21 membered heteroarylalkyl, e.g., the alkanyl, alkenyl or alkynyl moiety of the
heteroarylalkyl is (C1-C6) alkyl and the heteroaryl moiety is a 5-15-membered
heteroaryl. In particularly preferred embodiments, the heteroarylalkyl is a 6-13
membered heteroarylalkyl, eg., the alkanyl, alkenyl or alkynyl moiety is (C1-C3)
alkyl and the heteroaryl moiety is a 5-10 membered heteroaryl.
"Parent Aromatic Ring system" refers to an unsaturated cyclic or polycyclic
ring system having a conjugated n electron system. Specifically included within the
definition of "parent aromatic ring system" are fused ring systems in which one or
more of the rings are aromatic and one or more of the rings are saturated or
unsaturated, such as, for example, fluorene, indane, indene, phenalene, etc. Typical
parent aromatic ring systems include, but are not limited to, aceanthrylene,
acenaphthylene, acephenanthrylene, anthracene, azulene, benzene, chrysene, coronene,
fluoranthene, fluorene, hexacene, hexaphene, hexalene, as-indacene, s-indacene,
indane, indene, naphthalene, octacene, octaphene, octalene, ovalene, penta-2,4-diene,
pentacene, pentalene, pentaphene, perylene, phenalene, phenanthrene, picene,
pleiadene, pyrene, pyranthrene, rubicene, ttiphenylene, trinaphthalene and the like.
"Parent Heteroaromatic Ring system" refers to a parent aromatic ring system
in which one or more carbon atoms (and optionally any associated hydrogen atoms)
are each independently replaced with the same or different heteroatom. Typical
heteroatoms to replace the carbon atoms include, but are not limited to, N, P, O, S, Si,
etc. Specifically included within the definition of "parent heteroaromatic ring system"
are fused ring systems in which one or more of the rings are aromatic and one or more
of the rings are saturated or unsaturated, such as, for example, benzodioxan,
benzofuran, chromane, chromene, indole, indoline, xanthene, etc. Typical parent
heteroaromatic ring systems include, but are not limited to, arsindole, carbazole,
(5-carboline, chromane, chromene, cinnoline, furan, imidazole, indazole, indole,
indoline, indolizine, isobenzofuran, isochromene, isoindole, isoindoline, isoquinoline,
isothiazole, isoxazole, naphthyridine, oxadiazole, oxazole, perimidine, phenanthridine,
phenanthroline, phenazine, phthalazine, pteridine, purine, pyran, pyrazine, pyrazolc,
pyridazine, pyridine, pyrimidine, pyrrole, pyrrolizine, quinazoline, quinoline,
quinolizine, quinoxaline, tetrazole, thiadiazole, thiazole, thiophene, triazole, xanthene
and the like.
"Pharmaceutically acceptable salt" refers to a salt of a compound of the
invention which is made with counterfoils understood in the art to be generally
acceptable for pharmaceutical uses and which possesses the desired pharmacological
activity of the parent compound. Such salts include: (1) acid addition salts, formed
with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric
acid, phosphoric acid, and the like; or formed with organic acids such as acetic acid,
propionic acid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic acid,
lactic acid, malonic acid, succinic acid, malic acid, maleic acid, fumaric acid, tartaric
acid, citric acid, benzoic acid, 3-(4-hydroxybenzoyl) benzoic acid, cinnamic acid,
mandelic acid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonic acid,
2-hydroxyethanesulfbnic acid, benzenesulfonic acid, 4-chlorobenzenesulfonic acid,
2-naphthalenesulfonic acid, 4-toluenesulfonic acid, camphorsulfonic acid,
4-methyIbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic acid,
3-phenylpropionic acid, trimcthylacetic acid, tertiary butylacetic acid, lauryl sulfuric
acid, gluconic acid, glutamic acid, hydroxynaphthoic acid, salicylic acid, stearic acid,
muconic acid and the like; or (2) salts formed when an acidic proton present in the
parent compound is replaced by a metal ion, e.g., an alkali metal ion, an alkaline earth
ion, or an aluminum ion; or coordinates with an organic base such as ethanolamine,
diethanolamine, triethanolamine, N-methylglucamine, morpholine, piperidine,
dimethylamine, diethylaminc and the like. Also included are salts of amino acids such
as arginates and the like, and salts of organic acids like glucurmic or galactunoric acids
and the like (see, e.g., Berge et al., 1977, J. Pkarm. Sci. 66:1-19).
"Pharmacetically acceptable vehicle" refers to a diluent, adjuvant, excipient
or carrier with which a compound of the invention is administered.
"Protecting group" refers to a group of atoms that, when attached to a reactive
functional group in a molecule, mask, reduce or prevent the reactivity of the functional
group. Typically, a protecting group may be selectively removed as desired during the
course of a synthesis. Examples of protecting groups can be found in Greene and
Wuts, Protective Groups in Organic Chemistry, 3rd Ed., 1999, John Wiley & Sons, NY
and Harrison et al., Compendium of Synthetic Organic Methods, Vols. 1-8,1971-1996,
John Wiley & Sons, NY. Representative amino protecting groups include, but are not
limited to, formyl, acetyl, trifluoroacetyl, benzyl, benzyloxycarbonyl ("CBZ"),
tert-butoxycarbonyl ("Boc"), trimethylsilyl ("TMS"), 2-trimethylsilyl-ethanesulfonyl
("SES"), trityl and substituted trityl groups, allyloxycarbonyl,
9-fluorenylmethyloxycarbonyl ("FMOC"), nitro-veratryloxycarbonyl ("NVOC") and
the like. Representative hydroxyl protecting groups include, but are not limited to,
those where the hydroxyl group is either acylated (e.g., methyl and ethyl esters, acetate
or propionate groups or glycol esters) or alkylated such as benzyl and trityl ethers, as
well as alkyl ethers, tetrahydropyranyl ethers, trialkylsilyl ethers (e.g., TMS or TTPPS
groups) and allyl ethers.
"Prodrug" refers to a derivative of an active compound (drug) that undergoes a
transformation under the conditions of use, such as within the body, to release an
active drug. Prodrugs are frequently, but not necessarily, pharmacologically inactive
until converted into the active drug. Prodrugs are typically obtained by masking a
functional group in the drug believed to be in part required for activity with a progroup
(defined below) to form a promoiety which undergoes a transformation, such as
cleavage, under the specified conditions of use to release the functional group, and
hence the active drug. The cleavage of the promoiety may proceed spontaneously,
such as by way of a hydrolysis reaction, or it may be catalyzed or induced by another
agent, such as by an enzyme, by light, by acid, or by a change of or exposure to a
physical or environmental parameter, such as a change of temperature. The agent may
be endogenous to the conditions of use, such as an enzyme present in the cells to
which the prodrug is administered or the acidic conditions of the stomach, or it may be
supplied exogenously.
A wide variety of progroups, as well as the resultant promoieties, suitable for
masking functional groups in active compounds to yield prodrugs are well-known in
the art For example, a hydroxyl functional group may be masked as a sulfonate, ester
or carbonate promoiety, which may be hydrolyzed in vitro to provide the hydroxyl
group. An amino functional group may be masked as an amide, inline, phosphinyl,
phosphonyl, phosphoryl or sulfenyl promoiety, which may be hydrolyzed in vivo to
provide the amino group. A carboxyl group may be masked as- an ester (including
silyl esters and thioesters), amide or hydrazide promoiety, which may be hydrolyzed in
vivo to provide the carboxyl group. Other specific examples of suitable progroups and
their respective promoieties will be apparent to those of skill in the art
"Proeroup" refers to a type of protecting group that, when used to mask a
functional group within an active drug to form a promoiety, converts the drug into a
prodrug. Progroups are typically attached to the functional group of the drug via
bonds that are cleavable under specified conditions of use. Thus, a progroup is that
portion of a promoiety that cleaves to release the functional group under the specified
conditions of use. As a specific example, an amide promoiety of the formula
-NH-C(O)CH3 comprises the progroup -C(O)CH3.
"Substituted." when used to modify a specified group or radical, means that
one or more hydrogen atoms of the specified group or radical are each, independently
of one another, replaced with the same or different substituent(s). Substituent groups
useful for substituting saturated carbon atoms in the specified group or radical include,
but are not limited to -R', halo, -O', =0, -ORb, -SRb, -S-, =S, -NRcRC, =NRb, =N-0Rb,
trihalomethyl, -CF3, -CN, -OCN, -SCN, -NO, -NO2, =N2, -N3, S(O)2Rb -S(O)2O;
-S(O)20Rb, -OS(O)2Rb,-OS(0)2O-, -0S(O)2ORb, -P(O)(O)2, -P(O)(ORb)(O),
-P(O)(ORb)(ORb), -C(O)Rb, -C(S)Rb, -C(NRb)Rb, -C(O)O-, -C(O)ORb, -C(S)ORb,
-C(O)NRcRc, -C(NRb)NRcRc, -OC(O)Rb, -OC(S)Rb, -OC(O)O', -OC(O)ORb,
-OC(S)ORb, -NRbC(O)Rb, -NRbC(S)Rb, -NRbC(O)O-, -NRbC(O)ORb, -NRbC(S)ORb,
-NRbC(O)NRcRc, -NRbC(NRb)Rb and -NRbC(NRb)NRcRc, where Ra is selected from
the group consisting of alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl, aryl, arylalkyl,
heteroaryl and heteroarylalkyl; each Rb is independently hydrogen or R*; and each Rc
is independently Rb or alternatively, the two Rcs are taken together with the nitrogen
atom to which they are bonded form a S-, 6- or 7-membered cycloheteroalkyl which
may optionally include from 1 to 4 of the same or different additional heteroatoms
selected from the group consisting of O, N and S. As specific examples, -NRCRC is
meant to include -NH2, -NH-alkyl, N-pyrrolidinyl and N-morpholinyl.
Similarly, substituent groups useful for substituting unsaturated carbon atoms
in the specified group or radical include, but are not limited to, -R1, halo, -O", -0Rb,
-SRb, -S-, -NRcRC trihalomethyl, -CF3, -CN, -OCN, -SCN, -NO, -NO* -N3, -S(O)zRb,
-S(O)2O", -S(O)2ORb, -OS(O)2Rb, -OS(O)2O-, -OS(O)2ORb, -P(0)(0-)2,
-P(O)(ORb)(O), -P(O)(ORb)(ORb), -C(O)Rb, -C(S)Rb, -C(NRb)Rb, -C(O)O',
-C(O)ORb, -C(S)ORb, -C(O)NRCRC, -C(NRb)NCRC, -OC(O)Rb, -OC(S)Rb, -OC(O)O-,
-OC(O)ORb, -OC(S)ORb, -NRbC(O)Rb, -NRbC(S)Rb, -NRbC(O)O-, -NRbC(O)ORb,
-NRbC(S)ORb, -NRk0(O)NRCRC, -NRbC(NRb)Rb and -NRbC(NRb)NRcRc, where Ra,
Rb and Rc are as previously defined.
Substituent groups useful for substituting nitrogen atoms in heteroalkyl and
cycloheteroalkyl groups include, but are not limited to, -Ra -O-, -ORb, -SRb, -S-,
-NRCRC, trihalomethyl, -CF3, -CN, -NO, -NCb, -S(O)2Rb, -S(O)2O', -S(O)2ORb,
-OS(O)2Rb, -OS(O)2O', -0S(0)20Rb, -P(O)(O)2, -P(O)(ORb(O-), -P(O)(ORb)(ORb),
-C(O)Rb, -C(S)Rb, -C(NRb)Rb, -C(O)ORb, -C(S)ORb, -C(O)NRCRC, -C(NRb)NRcRc,
-OC(O)Rb, -OC(S)Rb, -OC(O)ORb, -OC(S)ORb, -NRbC(O)Rb, -NRbC(S)Rb,
-NRbC(O)ORb, -NRbC(S)ORb, -NRbC(O)NRcRc, -NRbC(NRb)Rb and -
NRbC(NRb)NRcRc, where Ra, Rb and Rc are as previously defined.
Substituent groups from the above lists useful for substituting other specified
groups or atoms will be apparent to those of skill in the art.
The substituents used to substitute a specified group can be further substituted,
typically with one or more of the same or different groups selected from the various
groups specified above.
"Sulfamovi." by itself or as part of another substituent, refers to a radical of the
formula -S(O)2NR'R", where R' and R" are each, independently of one another,
selected from the group consisting of hydrogen, alkyl and cycloalkyl as defined herein,
or alternatively, R' and R", taken together with the nitrogen atom to which they are
bonded, form a 5-, 6- or 7-membered cycloheteroalkyl ring as defined herein, which
may optionally include from 1 to 4 of the same or different additional heteroatoms
selected from the group consisting of O, S and N.
6.2 The Compounds
The invention provides substituted diphenyl heterocycle compounds
that are potent inhibitors of HCV replication and/or proliferation. In one embodiment,
the compounds of the invention are substituted diphenyl isoxazoles, pyrazoles and
oxadiazoles according to structural formula (I):
including the pharmaceutically acceptable salts, hydrates, solvates and
N-oxides thereof, wherein:
X and Y are each, independently of one another, N or O, provided that
X and Y are not both O;
Z is N or -CH-, provided that Z is -CH- when X and Y are both N;
R2, R3, R4, R5, R6, R8, R9, R10 and R13 are each, independently of one another,
selected from the group consisting of hydrogen, -OH, -SH, -CN, -NO2, halo, fluoro,
chloto, bromo, iodo, lower alkyl, substituted lower alkyl, lower heteroalkyl,
substituted lower heteroalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cycloheteroalkyl, lower haloalkyl, monohalomethyl, dihalomethyl,
trihalomethyl, trifiuoromethyl, lower alkylthio, substituted lower alkylthio, lower
alkoxy, substituted lower alkoxy, methoxy, substituted methoxy, lower heteroalkoxy,
substituted lower heteroalkoxy, cycloalkoxy, substituted cycloalkoxy,
cycloheteroalkoxy, substituted cycloheteroalkoxy, lower haloalkoxy,
monohalomethoxy, dihalomethoxy, trihalomethoxy, trifluoromethoxy, amino, lower
di- or monoalkylamino, substituted lower di- or monoalkylamino, aryl, substituted
aryl, aryloxy, substituted aryloxy, phenoxy, substituted phenoxy, arylalkyl, substituted
arylalkyl, arylalkyloxy, substituted arylalkyloxy, benzyl, benzyloxy, heteroaryl,
substituted heteroaryl, heteroaryloxy, substituted heteroaryloxy, heteroarylalkyl,
substituted heteroarylalkyl, heteroaryialkyloxy, substituted heteroarylalkyloxy,
carboxyl, lower alkoxycarbonyl, substituted lower alkoxycarbonyl, aryloxycarbonyl,
substituted aryloxycarbonyl, arylalkyloxycarbonyl, substituted arylalkyloxycarbonyl,
carbamate, substituted carbamate, carbamoyl, substituted carbamoyl, sulfamoyl,
substituted sulfamoyl and a group of the formula -1-R14, where "L" is a linker and RM
is cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl,
provided that at least one of R2 or R6 is other than hydrogen;
R11 is hydrogen or lower alkyl; and
R12 is monohalomethyl or dihalomethyl.
In the compounds of formula (I), one alternative group for substituents R2, R3,
R4, R5, R6, R8, R9, R10 and R13 is a group of the formula -1-R14, where "L" is a linker.
The linker may be any group of atoms suitable for attaching the R14 moiety to the
illustrated phenyl group. Suitable tinkers include, but are not limited to, moieties
selected from the group consisting of-(CH2)1-6-, O, S, -C(O)-, -SO2-, -NH-,
-NHC(O)-, -C(O)-, -SO2NH- and combinations thereof. In one embodiment, "L" is
selected from the group consisting of-(CH2)1-3-, -O-(CH2)1-3-, -S-(CH2)1-3- and -
SO2-.
In such L-R14 moieties, R14 is as defined above. In one embodiment, R14 is
selected from the group consisting of morpholinyl, N-morpholinyl, piperazinyl,
N-piperazinyl, N-methyl-N-piperazinyl, irnidazolinyl, N-imidazolidinyl,
N-methyl-N-imidazolidinyl, piperidinyl, N-pipcridinyi, pyrrolidinyl, N-pyrrolidinyl,
pyrazolidinyl, N-pyrazolidinyl and N-methyl-N-pyrazolidinyl.
In the compounds of formula (I), specific examples of substituent groups when
R2, R3, R4, R5, R6, R8, R9, R10 and/or R13 are a substituted alkyl group include methyl,
ethyl or propyl groups substituted with a single substituent selected from the group
consisting of halo, fluoro, chloro, bromo, hydroxy, lower alkoxy, -CN, -NO2,
-C(O)ORC, -OC(O)ORe, -C(O)NRfRg and -OC(O)NRfRg, where each Re is
independently hydrogen, lower alkyl or cycloaHcyl; and Rf and R8 are each,
independently of one another, selected from the group consisting of hydrogen, lower
alkyl and cycloalkyl or, alternatively, Rf and R8, taken together with the nitrogen atom
to which they are bonded form a 5-, 6- or 7-membered cycloheteroalkyl ring which
may optionally include from 1 to 4 of the same or different additional heteroatoms
selected from the group consisting of O, S and N. Further specific examples of
substituent groups when R2, R3, R4, R5, R6, R8, R9, R10 and/or R13 are a substituted
alkyl group include -CH2-R17, where R17 is halo, Br, -OH, lower alkoxy, -CN, NO2,
-C(O)RC, -OC(O)RC, -C(O)NRfRg and -OC(O)NRfRg, where Re, Rf and Rs are as
defined above.
Specific examples of substituent groups when R2, R3, R4, R5, R6, R8, R9, R10
and/or R13 are a substituted lower alkoxy group include lower alkoxy groups
substituted at the terminal methyl group with a substituent selected from the group
consisting of halo, -OH, -CN, -NO2, -C(O)Re, -OC(O)Re, -C(O)NRfRg and -
OC(O)NRfRg, where Re, Rf and Rg are as previously denned.
Specific examples of substituent groups when R2, R3, R4, R5, R6, R8, R9, R10
and/or R13 are aryl or heteroaryl groups include phenyl, 5- or 6-membered heteroaryl,
furanyl, imidazolyl, isotbiazolyl, isoxazolyl, pyranyl, pyrazinyl, pyrazolyl, pyridazinyl,
pyridinyl, pyrimidinyl, pyrrolyl and thiophcnyl. The various heteroaryl groups may be
connected to the remainder of the molecule via any available carbon atom or
heteroatom. In one embodiment, heteroaryl groups containing ring nitrogen atoms are
attached to the remainder of the molecule via a ring nitrogen atom. The heteroaryl
groups may also be substituted at one or more ring nitrogen atoms with a lower alkyl,
lower alkanyl or methyl group.
Specific examples of substituent groups when R2, R3, R4, R5, R6, R8, R9, R10
and/or R13 are carbamoyl or substituted carbamoyl groups include groups of the
formula -C(O)NRhR', where Rh and R' are taken together with the nitrogen atom to
which they are bonded to form a 5- or 6-membered cycloheteroalkyl ring which may
optionally include from 1 to 4 of the same or different additional heteratoms selected
from O, S and N and which is optionally substituted at one or more ring carbon or
heteratoms with a substituent selected from the group consisting of lower alkyl, lower
alkanyl, methyl, -OH, =0, -C(O)ORe, -C(O)NRfRg, -OC(O)RC, -OC(O)NRfR« and
aryl, where Rc, Rr and R8 are as previously defined. Further specific examples include
sulfamoyl or substituted sulfamoyl groups of the formula -C(0)NRhR', whereNRhR1
is selected from the group consisting of N-methyl-piperazine, 4-oxo-piperidine,
4-amino-piperdine, 4-(mono-or dialkylamino) piperidine and 4-hydroxy-piperdine.
Specific examples of substituent groups when R2, R3, R4, R5, R6, R8, R9, R10
and/or R13 are a substituted mono- or dialkylamino group include those mono or
dialkylamino groups in which at least one of the alkyl moieties is substituted,
preferably at a terminal methyl group, with a substituent selected from the group
consisting of-OH and -NR°Re, where each Re is as previously defined. Specific
examples of such substituted mono- and dialkylamino groups include -N(RkMCH2)1-
3-NRkRk and -N(Rk)(CH2)1-3-ORk, where each Rk is independently hydrogen, lower
alkyl or methyl.
Specific examples of substituent groups when R2, R3, R4, R5, R6, R8, R9, R10
and/or R13 is a cycloheteroalkyl or substituted cycloheteroalkyl group include 5- or 6-
membered cycloheteroalkyl, imidazolidinyl, morpholinyl, piperazinyl, piperadinyl,
pyrazotidinyl and pyrrolidinyl, wherein the ring may be optionally substituted at a ring
carbon atom with a substituent selected from the group consisting of-ORe, -NRfRg
and -C(O)ORe, where Re, Rf and Rs are as previously defined. The cycloheteroalkyl
or substituted cycloheteroalkyl may be attached to the remainder of the molecule via
any available ring carbon or heteroatom. hi one embodiment, the cycloheteroalkyl or
substituted cycloheteroalkyl is attached to the remainder of the molecule via a ring
nitrogen atom. Further specific examples of substituted cycloheteroalkyls suitable as
R2, R3, R4, R5, R6, R8, R9, R10 and/or R13 substituents include N-piperidinyl substituted
at the 4-position, or N-pyrrolidinyl substituted at the 3-position, with a lower
alkoxycarbonyl, amino, mono- or dialkylamino or N-piperidinyl group.
Additional specific examples of R2, R3, R4, R5, R6, R8, R9, R10 and R13, as well
as specific combinations of substituents for the "A" and "C" phenyl rings are provided
inTABLE 1,infra.
In one embodiment of the compounds of structural formula (I), Z is -CH- such
that the compounds are isoxazolcs or pyrazoles. In another embodiment of the
compounds of structural formula (I), Z is N such that the compounds are oxadiazoles.
In another embodiment, the compounds of structural formula (I) are isoxazoles.
In another embodiment of the compounds of structural formula (I), three of R8,
R9, R10 and R13 are hydrogen. In a specific embodiment, R9, R10 and R13 are each
hydrogen.
In yet another embodiment of the compounds of structural formula (I), R8, R9,
R10 and R13 are each, independently of one another, selected from the group consisting
of hydrogen, halo, fiuoro, chloro, bromo, iodo, sulfamoyl, lower alkylthio, lower
haloalkyl, monohalomethyl, dihalomethyl, trihalomethyl, trifluoromethyl and -1-R14,
where L is -(CH2)1-3- or -O-(CH2)1-3- and R14 is a 5- or 6-membered cycloheteroalkyl
or N-morpholinyl. In one specific embodiment, three of R8, R9, R10 and R13 are
hydrogen. In another specific embodiment, R9, R10 and R13 are each hydrogen.
In yet another embodiment of the compounds of structural formula (I), R2
and/or R6 are each, independently of one another, selected from the group consisting
of-OH, -NO2, halo, fiuoro, chloro, bromo, iodo, lower alkyl, methyl, lower
heteroalkyl, (C3-C6) cycloalkyl, 5- or 6-membered cycloheteroalkyl, N-morpholinyl,
N-methyl-N-piperazinyl, N-piperadinyl, substituted N-piperadinyl, 4-(N-piperadinyl)-
N-piperadinyl, 4-amino-N-piperadinyl, lower alkoxy, methoxy, ethoxy, lower
alkylthio, methylthio, lower haloalkyl, monohalomethyl, dihalomethyl, trihalomethyl,
trifluoromethyl, lower haloalkyloxy, monohalomethoxy, dihalomethoxy,
trihalomethoxy, trifluoromethoxy, aryl, phenyl, arylalkyl, benzyl, aryloxy, phenoxy,
arylalkyloxy, benzyloxy, 5- or 6-membered heteroaryl, lower alkyloxycarbonyl,
sulfamoyl and -1-R14, where L is -(CH2)1-3- or -O-(CH2)1-3- and R14 is a 5- or 6-
membered cycloheteroalkyl or N-morpholinyl.
In another embodiment of the compounds of structural formula (I), R3 and R5
are each, independently of one another, selected from the group consisting of
hydrogen, halo, fiuoro, chloro, lower alkoxyl, lower alkanyloxy, carboxyl, lower
alkanyloxycaibonyl, monohalomethyl, dihalomethyl, trihalomethyl and
trifluoromethyl.
In still another embodiment of the compounds of structural formula (I), R4 is
selected from the group consisting of hydrogen, lower dialkylamino, lower
dialkaylamino, dimethylamino, halo, fluoro, chloro and -1-R14, where L is
-O-(CH2)1-3- and R14 is 6-membered cycloheteroalkyl, N-morpholinyl or N-
piperazinyl.
In yet another embodiment of the compounds of structural formula (T), R3, R4,
R5, R8, R9, R10 and R13 are each hydrogen. Preferably, in this embodiment, R2 and R6
are each, independently of one another, selected from the group consisting of
hydroxyl, chloro, fluoro, methoxy, ethoxy, trifluoromethyl, trifluoromethoxy and
N-morpholinyl. In a specific embodiment, R2 and R6 are the same or different halo or
are each chloro. In another specific embodiment, R2 is fluoro and R6 is
trifluoromethyl. Preferably, in the above embodiments, Z is -CH- and/or X is N and
Y is O.
In still another embodiment, the compounds of the invention are compounds
according to structural formulae (Ia), (Ib), (Ic) and/or (Id):
including the phannaceutically acceptable salts, hydrates, solvates and N-
oxides thereof; wherein X, Y, R2, R3, R4, R5, R6, R11 and R12 are as previously defined
for structural formula (I) and subject to the same provisos. In one embodiment, the
compounds of structural formula (la), (Ib), (Ic) and/or (Id) have one or more features
selected from the group consisting of:
XisNandYisO;
XisOandYisN;
R11 is hydrogen or methyl;
R2 and R6 are each, independently of one another, selected from the
group consisting of hydrogen, hydroxyl, halo, lower alkyl, methyl, lower alkoxy,
methoxy, monohalomethyl, dihalomethyl, trihalomethyl, trifluoromethyl,
trifluoromethoxy, and N-morpholinyL, provided that at least one of R2 or R6 is other
than hydrogen;
R3 and R5 are each hydrogen; and
R4 is hydrogen or -1-R14, where L is -(CH2)1-3- and R14 is 6-membered
cycloheteroalkyL preferably comprising from 1 to 2 of the same or different
heteroatoms selected from O and N.
Exemplary compounds of the invention are provided in TABLE 1. Also
included in the invention are the various regioisomers of the compounds described
herein, including the various regioisomers of the compounds of structural formula (I),
(la), (Ib), (Ic), (Id) and TABLE 1.
Those of skill in the art will appreciate that the compounds of the invention
described herein may include functional groups that can be masked with progroups to
create prodrugs. Such prodrugs are usually, but need not be, pharmacologically
inactive until converted into their active drug form. In the prodrugs of the invention,
any available functional moiety may be masked with a progroup to yield a prodrug.
Myriad progroups suitable for masking such functional groups to yield promoieties
that are cleavable under the desired conditions of use are known in the art Specific
examples are described supra.
6.3 Methods of Synthesis
The compounds of the invention may be obtained via synthetic methods
illustrated in FIGS. 1-7. It should be understood that in FIGS. 1-7, R2, R3, R4, R5, R6,
R7, R8, R9, R10, R11, R12 and R13 are as previously defined for structural formula (I).
Starting materials useful for preparing compounds of the invention and
intermediates thereof are commercially available or can be prepared by well-known
synthetic methods (see, e.g., Harrison et ah, "Compendium of Synthetic Organic
Methods", Vols. 1-8 (John Wiley and Sons, 1971-1996); "Beilstein Handbook of
Organic Chemistry," Beilstein Institute of Organic Chemistry, Frankfurt, Germany;
Feiser et al, "Reagents for Organic Synthesis," Volumes 1-21, Wiley mterscience;
Trost et al, "Comprehensive Organic Synthesis," Pergamon Press, 1991;
Theilheimer's Synthetic Methods of Organic Chemistry," Volumes 1-45, Karger,
1991; March, "Advanced Organic Chemistry," Wiley wterscience, 1991; Larock
"Comprehensive Organic Transformations," VCH Publishers, 1989; Paquette,
"Encyclopedia of Reagents for Organic Synthesis," 3d Edition, John Wiley & Sons,
1995). Other methods for synthesis of the compounds described herein and/or starting
materials are either described in the art or will be readily apparent to the skilled
artisan. Alternatives to the reagents and/or protecting groups illustrated in FIGS. 1-7
may be found in the references provided above and in other compendiums well known
to the skilled artisan. Guidance for selecting suitable protecting groups can be found,
for example, in Greene & Wuts, "Protective Groups in Organic Synthesis," Wiley
Intcrscience, 1999. Accordingly, the synthetic methods and strategy presented herein
are illustrative rather than comprehensive.
One method for synthesizing substituted diphenyl isoxazoles according to
structural formula (I) (when Z is -CH-) is provided in FIG. 1 A. Referring to FIG. 1 A,
aldol condensation of methyl ketone 201 with benzaldehyde 203 under basic
conditions, followed by in situ dehydration, provides ct-p unsaturated enone 205,
which may be readily converted to isoxazole 207 by treatment with hydroxylamine.
Reduction of 207 yields the amino isoxazole 209, which may be optionally alkylated
with R11-halide and acylated with LG-C(O)-R12 yield 211. In FIG. 1A and throughout
the remaining FIGS. 2-7, "LG" represents a leaving or activating group, regardless of
the moiety to which it is attached. Myriad suitable leaving and activating groups are
known to those of skill in the art. Specific examples useful in the various methods
described herein include, but are not limited to, halo, cyano, acyloxy and the myriad
other leaving groups known to those of skill in the art to be useful in the formation of
amide bonds.
A specific example of the synthetic method of FIG. 1A is illustrated for the
preparation of diphenyl isoxazole 9 in FIG. IB.
Another method for synthesizing substituted isoxazoles of structural formula
(I) (when Z is -CH-) is provided in FIG. 2A. Claisen condensation of methyl ketone
201 with ester 223 under basic conditions provides 1,3 diketone' 229, which may be
converted to a mixture of isoxazoles 207 and 231 by treatment with hydroxylamine.
Isolation and subsequent reduction of 207 yields the amino isoxazole 209, which may
be transformed to the isoxazole 211 as previously described or by other well known
synthetic methods. It should be noted that isoxazole 231 may be isolated and
converted to the corresponding regioisomer of isoxazole 211 (compound 212) by the
same synthetic pathway. A specific example of the synthetic method of FIG. 2A is
illustrated for the preparation of diphenyl isoxazole 9 and its corresponding
regioisomers 5 in FIG. 2B.
In alternative embodiment of the pathway illustrated in FIG. 2A, ester 225 is
condensed with methyl ketone 227 to provide 1,3 diketone 229, which is then carried
through the remainder of the synthetic pathway as previously described.
Still another method for synthesizing substituted isoxazoles of structural
formula (I) (when Z is -CH-) is provided in FIG. 3 A. Nucleophilic addition of
hydroxylamine to benzaldehyde 245 provides an intermediate oxime, which may be
converted by treatment with N-chlorosoccinimide (NCS) or other methods known in
the art to the a-chlorooxime 247. Dehydrohalogenation of a-chlorooxime 247 in the
presence of a base yields nitrile oxide 248a or 248b, which undergoes 1,3 dipolar
cycloaddition in the presence of acetylene 249 to provide the desired isoxazole 211.
As will be recognized by skilled artisans, the nitrile oxide 248a or 248b can be
isolated prior to cycloaddition with acetylene 249 or, alternatively, acetylene 249 may
be added directly to the reaction mixture without first isolating the nitrile oxide 248a
or 248b. Acetylene 249 may be readily prepared from commercially available
precursors by well known synthetic methods. Specific methods are provided in FIG.
7A and 7B. A specific example of the synthetic method of FIG. 3A is illustrated for
the preparation of diphenyl isoxazole 9 in FIG. 3B.
Methods for preparing nitrile oxide 248a or 248b are illustrated in FIG. 3C.
Referring to FIG. 3C, myriad different types of benzylic compounds 303 are converted
to the benzylic nitro compound 305 using standard techniques. Treatment with phcnyl
isocyanate in the presence of a weak base yields nitrile oxide 248a or 248b. 1,3-
Dipolar cycloaddition with acetylene 309 yields isoxazole 311. In acetylene 309 and
isoxazole 311, R15 is -NO2, -NHR or-NR11C(O)R12, where R is hydrogen, lower alkyl
or a protecting group and R11 and R12 are as previously defined for structural formula
(I). Depending upon the identity of R15, isoxazole 311 is then converted to isoxazole
211 using the previously described methods.
Still another method for synthesizing substituted isoxazoles of structural
formula (I) (when Z is -CH-) is provided in FIG. 4A. Nucleophilic addition of
hydroxylamine to benzaldehyde 245 provides an intermediate oxime, which may be
directly converted to nitrile oxide 248a or 248b with NaOCl in the presence of NaOH.
1,3 Dipolar cycloaddition of nitrile oxide 248a or 248b to methyl ketone 259 provides
desired isoxazole 211. Methyl ketone 259 may be readily prepared from commercially
available precursors by well known synthetic methods. A specific example of the
synthetic method of Figure 4A is illustrated for the preparation of diphenyl isoxazole 9
in FIG. 4B.
The methods described in FIGS. 1-4 above may be readily adapted for the
synthesis of pyrazoles by substituting hydrazine for hydroxylamine in the reaction
nn
sequence. Further, those of skill in the art will appreciate that isoxazole regioisomers
of those depicted in the above FIGS. 1-4 may be synthesized by merely interchanging
the reactive functionalities of the two different aromatic rings. An example of this
approach is depicted in FIG. 4C for "reverse" isoxazole 5. As can be seen in FIG. 4C,
interchanging the chlorooxime and alkyne functionalities of the two different aromatic
rings (i.e., rings A and C) provides the regioisomeric isoxazole 5 (compare 253 and
255 with 254 and 256). Further, certain synthetic schemes may provide both isoxazole
regioisomers (e.g., FIG. 2A and 2B) directly, which may be isolated from one another
using standard techniques.
One method for synthesizing substituted oxadiazoles of structural formula (1)
(when Z is -N-) is provided in FIG. 5A. Referring to FIG. 5A, nucleophilic addition of
hydroxylamine to phenyl cyanide 265 yields the amide oxime 267, which may be
condensed with compound 269 to provide oxadiazole 271 after dehydrative cyclization
and reduction. Amino oxadiazole 271 may be optionally alkylated followed by
acylation, as described above, to yield oxadiazole 273. A specific example of the
synthetic method of FIG. 5A is illustrated for the preparation of diphenyl oxadiazole
25 in FIG. 5B.
Another method for synthesizing substituted oxadiazoles of structural formula
(I) (when Z is -N-), which are regioisomers of those prepared above, is provided in
FIG. 6A. Referring to FIG. 6A, amide oxime 287, (prepared by condensation of
hydroxyl amine with a phenyl cyanide), may be condensed with acylating agent 285,
which may be an acyl chloride, to provide oxadiazole 289 after dehydrative cyclization
and reduction. Amino oxadiazole 289 may be transformed by the previously described
methods to final product 291. A specific example of the synthetic method of FIG. 6A
is illustrated for the preparation of diphenyl oxadiazole 87 in FIG. 6B.
FIGS. 7A and 7B, which describe the preparation of acetylene compounds, are
discussed in the Examples section.
In FIGS. 1-7, substituents R2, R3, R4, R5, R6, R8, R9, R10 and R13 may include
reactive functional groups that require protection during synthesis. Selection of
suitable protecting groups will depend on the identity of the functional group and the
synthesis method employed, and will be apparent to those of skill in the art. Guidance
for selecting suitable protecting groups can be found in Greene & Wuts, supra, and the
various other references cited therein.
Further guidance for carrying out 1,3-dipolar cycloaddition reactions, also
named 1,3-dipolar additions, [3+2] cyclizations or [3+2] cycloadditions, can be found
in "Cycloaddition Reactions in Organic Synthesis", (Kobayashi, S. and Jorgensen, K.
A., Editors), 2002, Wiley-VCH Publishers, pp. 1 - 332 pages (specifically, Chapters 6
and 7 on [3+2] cycloadditions and 1,3-dipolar additions, pp. 211 - 248 and 249 - 300);
"1,3-Dipolar Cycloaddition11, Chemistry ofHeterocyclic Compounds, Vol. 59, (Padwa,
A. and Pearson, W., Editors), 2002, John Wiley, New York, pp. 1-940; "Nitrite
Oxides, Nitrones, Nitronates in Organic Synthesis: Novel Strategies in Synthesis",
Torssel, K. B. G., 1988, VCH Publishers, New York, pp. 1-332; Barnes & Spriggs,
1945,/. Am. Chan Soc. 67:134; and Anjaneyulu et al., 1995, Indian J. Chem., Sect 5
34(11):933-938).
Further guidance for synthesizing isoxozoles may be found in M.
Sutharchanadevi, R. Murugan in Comprehensive Heterocyclic Chemistry II, A.R.
Katritzky, C.W. Rees, E.F.V. Scriven, Eds.; Pergamon Press, Oxford, Vol. 3, p. 221;
R. Grunager, P, Vita-Finzi in Heterocyclic Compounds, Vol. 49, Isoxazoles, Part one,
John Wiley and Sons, New York, 1991; K. B. G. Torssell, Nitrile Oxides, Nitrones,
and Nitronates in Organic Synthesis, VCH Publishers, New York, 1988; Y-Y. Ku, T.
Grieme, P. Shanna,, Y.-M. Pu, P. Raje, H. Morton, S. King Organic Letters, 2001,3,
4185; V. G. Etesai, S. G. Tilve Synth. Comm., 1999,29,3017; X. Wei, J. Fang, Y. Hu,
H. Hu Synthesis, 1992,1205; C. Kashima, N. Yoshihara, S. Shirai Heterocycles,
1981,16,145; A.S.R. Anjaneyulu, G.S. Rani, K.G. Annapuma, U. V. Matlavadhani,
Y.L.N. Murthy Indian J. Chem. SectB, 1995,34,933; R.P. Barnes, A.S. Spriggs, J.
Am. Chem. Soc., 1945,67,134; A. Albetola, L. Calvo, A.G. Ortega, MX. Sabada,
M.C. Safludo, S.G. Granda, E.'G. Rodriguez Heterocycles, 1999,51,2675; X. Wang, J.
Tan, K. Grozinger Tetrahedron Lett. 2000,41,4713; A. R. Katritzky, M. Wang, S.
Zhang, M.V. Voronkov J. Org. Chem., 2001,66,6787; and J. Bohrisch, M. PStzel, C.
Mügge, J. Iiebscher Synthesis, 1991,1153.. Further guidance for synthesizing
pyrazoles may be found in J. Elguero in Comprehensive Heterocyclic Chemistry II,
A.R. Katritzky, C.W. Reees, E.F.V. Scriven., Eds.; Pergamon Press, Oxford, 1996;
Vol.3,p.l.
6.4 Assays For Modulation Of HCV
The compounds of the invention are potent inhibitors of HCV
replication and/or proliferation. The activity of the compounds of the invention can be
confirmed in in vitro assays suitable for measuring inhibition of viral or retro viral
replication and/or proliferation. The assays may investigate any parameter that is
directly or indirectly under the influence of HCV, including, but not limited to,
protein-RNA binding, translation, transcription, genome replication, protein
processing, viral particle formation, infectivity, viral transduction, etc. Such assays
are well-known in the art. Regardless of the parameter being investigated, in one
embodiment, to examine the extent of inhibition, samples, cells, tissues, etc.
comprising an HCV replicon or HCV RNA are treated with a potential inhibitory
compound (test compound) and the value for the parameter compared to control cells
(untreated or treated with a vehicle or other placebo). Control samples are assigned a
relative activity value of 100%. Inhibition is achieved when the activity value of the
test compound relative to the control is about 90%, preferably 50%, and more
preferably 25-0%.
Alternatively, the extent of inhibition may be determined based upon the ICso
of the compound in the particular assay, as will be described in more detail, below.
In one embodiment, the inhibitory activity of the compounds can be confirmed
in a replicon assay that assesses the ability of a test compound to block or inhibit HCV
replication in replicon cells. One example of a suitable replicon assay is the liver cell-
line Huh 7-based replicon assay described in Lohmann et al., 1999, Science 285:110-
113. A specific example of this replicon assay which utilizes luciferase translation is
provided in the Examples Section. In one embodiment of this assay, the amount of
test compound mat yields a 50% reduction in translation as compared to a control cell
(ICso) may be determined.
Alternatively, the inhibitory activity of the compounds can be confirmed using
a quantitative Western immunoblot assay utilizing antibodies specific for HCV non-
structural proteins, such as NS3, NS4A NS5A and NS5B. La one embodiment of this
assay, replicon cells are treated with varying concentrations of test compound to
determine the concentration of test compound that yields a 50% reduction in the
amount of a non-structural protein produced as compared to a control sample (ICjo)-
A single non-structural protein may be quantified or multiple non-structural proteins
may be quantified. Antibodies suitable for carrying out such immunoblot assays are
available commercially (e.g., from BIODESIGN International, Saco, ME).
Alternatively, the inhibitory activity of the compounds may be confirmed in an
HCV infection assay, such as the HCV infection assay described in Fournier et al.,
1998, J. Gen. Virol. 79(10):2367:2374, the disclosure of which is incorporated herein
by reference. In one embodiment of this assay, the amount of test compound mat
yields a 50% reduction in HCV replication or proliferation as compared to a control
cell (IC50) may be determined. The extent of HCV replication may be determined by
quantifying the amount of HCV RNA present in HCV infected cells. A specific
method for carrying out such an assay is provided in the Examples section.
As yet another example, the inhibitory activity of the compounds can be
confirmed using an assay that quantifies the amount of HCV RNA transcribed in
treated replicon cells using, for example, a Taqman assay (Roche Molecular, Alameda,
CA). In one embodiment of this assay, the amount of test compound that yields a 50%
reduction in transcription of one or more HCV RNAs as compared to a control sample
(IC30) may be determined.
Regardless of the assay used, active compounds are generally those which
exhibit IC50s in the particular assay in the range of about 1 mM or less. Compounds
which exhibit lower IC50S, for example, in the range of about 100µM, 10 µM, 1 µM,
100 nM, 10 nM, 1 nM, or even lower, are particularly useful for as therapeutics or
prophylactics to treat or prevent HCV infections.
6.5 Uses and Administration
Owing to their ability to inhibit HCV replication, the compounds of the
invention and/or compositions thereof can be used in a variety of contexts. For
example, the compounds of the invention can be used as controls in in vitro assays to
identify additional more or less potent anti HCV compounds. As another example, the
compounds of the invention and/or compositions thereof can be used as preservatives
or disinfectants in clinical settings to prevent medical instruments and supplies from
becoming infected with HCV virus. When used in this context, the compound of the
invention and/or composition thereof may be applied to the instrument to be
disinfected at a concentration that is a multiple, for example IX, 2X, 3X, 4X, 5X or
even higher, of the measured IC50 for the compound
In a specific embodiment, the compounds and/or compositions can be used to
"disinfect" organs for transplantation. For example, a liver or portion thereof being
prepared for transplantation can be perfused with a solution comprising an inhibitory
compound of the invention prior to implanting the organ into the recipient This
method has proven successful with lamuvidine (3TC, Epivir®, Epivir-HB®) for
reducing the incidence of hepatitis B virus (HBV) infection following liver transplant
surgery/therapy. Quite interestingly, it has been found that such pertusion therapy not
only protects a liver recipient free of HBV infection (HBV-) from contracting HBV
from a liver received from an HBV+ donor, but it also protects a liver from an HBV-
donor transplanted into an HBV+ recipient from attack by HBV. The compounds of
the invention may be used in a similar manner prior to organ or liver transplantation.
The compounds of the invention and/or compositions thereof find particular
use in the treatment and/or prevention of HCV infections in animals and humans.
When used in this context, the compounds may be administered per se, but are
typically formulated and administered in the form of a pharmaceutical composition.
The exact composition will depend upon, among other things, the method of
administration and will apparent to those of skill in the art. A wide variety of suitable
pharmaceutical compositions are described, for example, in Remington's
Pharmaceutical Sciences, 20th ed., 2001).
Formulations suitable for oral administration can consist of (a) liquid solutions,
such as an effective amount of the active compound suspended in diluents, such as
water, saline or PEG 400; (b) capsules, sachets or tablets, each containing a
predetermined amount of the active ingredient, as liquids, solids, granules or gelatin;
(c) suspensions in an appropriate liquid; and (d) suitable emulsions. Tablet forms can
include one or more of lactose, sucrose, mannitol, sorbitol, calcium phosphates, corn
starch, potato starch, microcrystalline cellulose, gelatin, colloidal silicon dioxide, talc,
magnesium stearate, stearic acid, and other excipients, colorants, fillers, binders,
diluents, buffering agents, moistening agents, preservatives, flavoring agents, dyes,
disintegrating agents, and pharmaceutically compatible carriers. Lozenge forms can
comprise the active ingredient in a flavor, e.g., sucrose, as well as pastilles comprising
the active ingredient in an inert base, such as gelatin and glycerin or sucrose and
acacia emulsions, gels, and the like containing, in addition to the active ingredient,
carriers known in the art.
The compound of choice, alone or in combination with other suitable
components, can be made into aerosol formulations (i.e., they can be "nebulized") to
be administered via inhalation. Aerosol formulations can be placed into pressurized
acceptable propellents, such as dichlorodifluoromethane, propane, nitrogen, and the
like.
Suitable formulations for rectal administration include, for example,
suppositories, which consist of the packaged nucleic acid with a suppository base.
Suitable suppository bases include natural or synthetic triglycerides or paraffin
hydrocarbons, In addition, it is also possible to use gelatin rectal capsules which
consist of a combination of the compound of choice with a base, including, for
example, liquid triglycerides, polyethylene glycols, and paraffin hydrocarbons.
Formulations suitable for parenteral administration, such as, for example, by
intraarticular (in the joints), intravenous, intramuscular, intradermal, intraperitoneal,
and subcutaneous routes, include aqueous and non-aqueous, isotonic sterile injection
solutions, which can contain antioxidants, buffers, bacteriostats, and solutes that
render the formulation isotonic with the blood of the intended recipient, and aqueous
and non-aqueous sterile suspensions that can include suspending agents, solubilizers,
thickening agents, stabilizers, and preservatives. In the practice of this invention,
compositions can be administered, for example, by intravenous infusion, orally,
topically, intraperitoneally, intravesically or intrathecally. Parenteral administration,
oral administration, subcutaneous administration and intravenous administration are
the preferred methods of administration. A specific example of a suitable solution
formulation may comprise from about 0.5-100 mg/ml compound and about 1000
mg/ml propylene glycol in water. Another specific example of a suitable solution
formulation may comprise from about 0.5-100 mg/ml compound and from about 800-
1000 mg/ml polyethylene glycol 400 (PEG 400) in water.
A specific example of a suitable suspension formulation may include from
about 0.5-30 mg/ml compound and one or more excipents selected from the group
consisting of: about 200 mg/ml ethanol; about 1000 mg/ml vegetable oil (e.g., com
oil), about 600-1000 mg/ml fruit juice (e.g., grapefruit juice), about 400-800 mg/ml
milk, about 0.1 mg/ml carboxymethylcellulose (or microcrystaUine cellulose), about
0.5 mg/ml benzyl alcohol (or a combination of benzyl alcohol and benzalkonium
chloride) and about 40-50 mM buffer, pH 7 (e.g., phosphate buffer, acetate buffer or
citrate buffer or, alternatively 5% dextrose may be used in place of the buffer) in
water.
A specific example of a suitable liposome suspension formulation may
comprise from about 0.5-30 mg/ml compound, about 100-200 mg/ml lecithin (or other
phospholipid or mixture of phospholipids) and optionally about 5 mg/ml cholesterol in
water. For subcutaneous administration of compound 9, a liposome suspension
formulation including 5 mg/ml compound in water with 100 mg/ml lecithin and 5
mg/ml compound in water with 100 mg/ml lecithin and 5 mg/ml cholesterol provides
good results. This formulation may be used for other compounds of the invention.
The formulations of compounds can be presented in unit-dose or multi-dose
sealed containers, such as ampules and vials. Injection solutions and suspensions can
be prepared from sterile powders, granules, and tablets of the kind previously
described.
The pharmaceutical preparation is preferably in unit dosage form. In such
form the preparation is subdivided into unit doses containing appropriate quantities of
the active component The unit dosage form can be a packaged preparation, the
package containing discrete quantities of preparation, such as packeted tablets,
capsules, and powders in vials or ampoules. Also, the unit dosage form can be a
capsule, tablet, cachet, or lozenge itself, or it can be the appropriate number of any of
these in packaged form. The composition can, if desired, also contain other
compatible therapeutic agents, discussed in more detail, below.
In therapeutic use for the treatment of HCV infection, the compounds utilized
in the pharmaceutical method of the invention are administered to patients diagnosed
with HCV infection at dosage levels suitable to achieve therapeutic benefit By'
therapeutic benefit is meant that the administration of compound leads to a beneficial
effect in the patient over time. For example, therapeutic benefit is achieved when the
HCV titer or load in the patient is either reduced or stops increasing. Therapeutic
benefit is also achieved if the administration of compound slows or halts altogether the
onset of the organ damage that or other adverse symptoms typically accompany HCV
infections, regardless of the HCV titer or load in the patient.
The compounds of the invention and/or compositions thereof may also be
administered prophylactically in patients who are at risk of developing HCV infection,
or who have been exposed to HCV, to prevent the development of HCV infection. For
example, the compounds of the invention and/or compositions thereof may be
administered to hospital workers accidentally stuck with needles while working with
HCV patients to lower the risk of, or avoid altogether, developing an HCV infection.
Initial dosages suitable for administration to humans may be determined from
in vitro assays or animal models. For example, an initial dosage may be formulated to
achieve a serum concentration that includes the ICso of the particular compound being
administered, as measured in an in vitro assay. Alternatively, an initial dosage for
humans may be based upon dosages found to be effective in animal models of HCV
infectioa Exemplary suitable model systems are described, for example, in
Muchmore, 2001, Immunol. Rev. 183:86-93 and Lanfoid & Bigger, 2002, Virology,
293:1-9, and the referenced cited therein. As one example, the initial dosage may be
in the range of about 0.01 mg/kg/day to about 200 mg/kg/day, or about 0.1 mg/kg/day
to about 100 mg/kg/day, or about 1 mg/kg/day to about SO mg/kg/day, or about 10
mg/kg/day to about SO mg/kg/day, can also be used. The dosages, however, may be
varied depending upon the requirements of the patient, the severity of the condition
being treated, and the compound being employed. The size of the dose also will be
determined by the existence, nature, and extent of any adverse side-effects that
accompany the administration of a particular compound in a particular patient
Determination of the proper dosage for a particular situation is within the skill of the
practitioner. Generally, treatment is initiated with smaller dosages which are less than
the optimum dose of the compound. Thereafter, the dosage is increased by small
increments until the optimum effect under circumstances is reached. For convenience,
the total daily dosage may be divided and administered in portions during the day, if
desired.
6.6 Combination Therapy
In certain embodiments of the present invention, the compounds of the
invention and/or compositions thereof can be used in combination therapy with at least
one other therapeutic agent. A compound of the invention and/or composition thereof
and the therapeutic agent can act additively or, more preferably, synergistically. The
compound of the invention and/or a composition thereof may be administered
concurrently with the administration of the other therapeutic agent(s), or it may be
administered prior to or subsequent to administration of the other therapeutic agent(s).
In one embodiment, the compounds of the invention and/or compositions
thereof are used in combination therapy with other antiviral agents or other therapies
known to be effective in the treatment or prevention of HCV. As a specific example,
the compounds of the invention and/or compositions thereof may be used in
combination with known antivirals, such as ribavirin (see, e.g., US Patent No.
4,530,901). As another specific example, the compounds of the invention and/or
compositions thereof may also be administered in combination with one or more of the
compounds described in any of the following: U.S. Patent No. 6,143,715; U.S. Patent
No. 6,323,180; U.S. Patent No. 6,329,379; U.S. Patent No. 6,329,417; U.S. Patent No.
6,410,531; U.S. Patent No. 6,420,380; and U.S. Patent No. 6,448,281.
Yet another specific example, the compounds of the invention and/or
compositions thereof may be used in combination with interferons such as
a-interferon, b-interferon and/or ?-interferon. The interferons may be unmodified,
or may be modified with moieties such as polyethylene glycol (pegylated interferons).
Many suitable unpegylated and pegylated interferons are available commercially, and
include, by way of example and not limitation, recombinant interferon alpha-2b such
as Intron-A interferon available from Schering Corporation, Kenilworth, N.J.,
recombinant interferon alpha-2a such as Roferon interferon available from Hoflmann-
La Roche, Nutley, N.JU., recombinant interferon alpha-2C such as Berofor alpha 2
interferon available from Boehringer Ingelheim Pharmaceutical, Inc., Ridgefield,
Conn., interferon alpha-nl, a purified blend of natural alpha interferons such as
Sumiferon available from Sumitomo, Japan or as Wellferon interferon alpha-nl (INS)
available from the Glaxo-Wellcome Ltd., London, Great Britain, or a consensus alpha
interferon such as those described in U.S. Pat Nos. 4,897,471 and 4,695,623
(especially Examples 7,8 or 9 thereof) and the specific product available from Amgen,
Inc., Newbury Park, Calif., or interferon alpha-n3 a mixture of natural alpha
interferons made by Interferon Sciences and available from the Purdue Frederick Co.,
Norwalk, Conn., under the Alferon Tradename, pegylated interferon-2b available from
Schering Corporation, Kenilworth, N. J. under the tradename PEG-Intron A and
pegylated interferon-2a available from Hoffinan-LaRoche, Nutley, N.J. under the
tradename Pegasys.
As yet another specific example, the compounds of the invention and/or
compositions thereof may be administered in combination with both ribovirin and an
interferon.
7. EXAMPLES
The following examples are provided by way of illustration only and not by
way of limitation. Those of skill in the art will readily recognize a variety of
noncritical parameters that could be changed or modified to yield essentially similar
results
7.1 Compound Syntheses
The compounds of TABLE 1 were synthesized according to the methods
described below or illustrated in FIGS. 1-7. Melting points were obtained on an
Electrothermal IA9100 series digital melting point apparatus. All Melting points are
uncorrected. NMR spectra were obtained on a 300 MHz Varian Mercury system. LC-
MS was performed on a Waters Micromass ZQ instrument with electrospray
ionization. The HPLC component was a Waters Model 2690 Separation module
coupled to a Waters Model 996 photodiode array detector. The specific LC-MS
method used to analyze particular compounds, indicated for each compound in
parentheses, are provided below:
Method W
This method utilized a 2.1x250 mm 5 µm C-18 Altima reversed phase column
(Alltech) with a flow rate of 0.25 mL/min and a gradient of 5-85% acetonitrile with
water containing 0.1 % trifluoroacetic acid over 36 min. The gradient then ramps to
100% acetonitrile over 0.5 min and continues at 100% acetonitrile for 3.5 min.
Method X
This method utilized a 2.1x250 mm 5 µm C-18 Altima reversed phase column
(Alltech) with a flow rate of 0.25 mL/min and a gradient of 5-85% acetonitrile with
water containing 0.1% trifluoroacetic acid over 15 min. The gradient men ramps to
100% acetonitrile over 0.5 min and continues at 100% acetonitrile for 2.5 min.
Method Y
This method utilized a 2.1x150 mm Agilent Zorbax 5 µm C-18 reversed phase
column with a flow rate of 0.3 mL/min and a gradient of 10-100% acetonitrile with
water containing 0.1% trifluoroacetic acid over 16 min, then continuing for 2 min with
100% acetonitrile.
Method Z
This method utilized a 2.1x5 mm Agilent Zorbax 5 M C-l 8 reversed phase
column with a flow rate of 0.5 mL/min and a gradient of 5-100% acetonitrile with
water containing 0.1 % trifluoroacetic acid over 8 min, then continuing for 2 min with
100%acetonitrile.
Synthesis of 2,2-DichIoro-N-[3-(3-(2,6-dichlorophenyl)-5-isoiazoIyI]phenyl]
Acetamide (Compound 9)
Synthesis of 2,6-Dichloro-N-hydroxybenzenecarboximidoyl Chloride
The general procedure of R.K. Howe et al, J. Org. Chem.. 1980,45,3916-3918
was followed. 2,6-Dichlorobenzaldoxime (25.1 gm, 0.132 mol) was dissolved in
DMF (1 SO mL). Then N-chlorosuccinimide (approximately 1.5 g) was added. After
several minutes the reaction was heated until the internal temperature reached 50 °C.
Then the remainder of the N-chlorosuccinimide was added in small portions to a total
of 17.6 g (0.132 mol), keeping the reaction temperature at 40-50 °C. After the addition
was complete, the reaction was allowed to stir for 0.5h, then was diluted with 600 mL
of water. The mixture was extracted twice with ether. The combined ether extracts
were washed three times with water, dried over anhydrous sodium sulfate, filtered and
concentrated under reduced pressure. The residue was concentrated under vacuum to
give the title a-chlorooxime as a white solid (m.p. 89-90 °Q. NMR (300 MHz,
CDC13): 7.98 (s, 1H, exchanges with D2O), 7.3-7.4 ppm (m, 3H).
Synthesis of 2,2-Dichloro-N-(3-ethynyIphenyl) Acetamide
3-Ethynylaniline (2.61 g, 22.3 mmol) was dissolved in anhydrous
dichloromethane (20 mL) with triethylamine (3.1 mL, 22.3 mmol). The mixture was
cooled in an ice-bath under nitrogen, then a solution of dichloroacetyl chloride (221
mL, 23 mmol) in anhydrous dichloromethane (20 mL) was added dropwise. After the
addition was completed the ice-bam was removed and the mixture was stirred at room
temperature for 2h. The reaction mixture was then washed successively with water,
10% hydrochloric acid and saturated sodium bicarbonate solution. The organic
solution was dried over anhydrous sodium sulfate, filtered and concentrated under
reduced pressure to give the title compound as a beige solid (m.p. 99-100 °C). NMR
(300 MHz, CDCl3): 8.05 (broad s, 1H, NH), 7.69 (s, 1H), 7.62 (m, 1H), 7.33 (m, 2H),
6.04 (s, 1H), 3.10 ppm (s, 1H, acetylenic).
Synthesis of 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-S-
isoxazolyl]phenyl] Acetamide (Compound 9)
2,6-Dichloro-N-hydroxybenzoiecarboxnnidoyl chloride (2.72 g, 95.6 mmol)
and 2,2-dichloro-N-(3-ethynylphenyl) acetamide (2.5 g, 110 mmol) were dissolved in
anhydrous THF (40 mL) and triethylamine (1.8 mL). The mixture was stirred at room
temperature for In then heated at reflux for 5h to generate the 2,6-dichlorophenyl
nitrile oxide intermediate, which reacted by a 1,3-dipolar cycloaddition reaction with
2,2-dichloro-N-(3-ethynylphenyl) acetamide. The solvent was removed under reduced
pressure. The residue was dissolved in ethyl acetate and washed successively with
water and brine. The ethyl acetate solution was dried over anhydrous sodium sulfate,
filtered and concentrated under reduced pressure. The resulting solid was purified by
column chromatography on silica gel, eluting with 8:2 hexanes-efhyl acetate. The
appropriate fractions were combined and men crystallized from hexanes-ethyl acetate
to give 2,2-dichloro-N-[3-[3-(2,6-dchlorophenyl)-5-isoxazolyl]phenyl] acetamide as a
white crystalline solid, 1.80 g (m.p. 167 °C). NMR (300 MHz, CDC13): 8.21 (broad s,
1H, NH), 8.08 (m, 1H), 7.71 (m, 2H), 7.52 (t, 1H), 7.42-7.46 (m, 2H), 7.32-7.38 (m,
1H), 6.69 (s, 1H), 6.07 ppm (s, 1H). MW=416 confirmed by LC-MS, V=36.9 min
(Method W) MH+=415-419.
Oxime Formation (Step 1 of FIG. 3A)
METHOD A
Referring to Fig. 3 A, the aldehyde starting material 245 was dissolved in
pyridine solvent, and 1.0-1.2 equivalents of solid hydroxylamine hydrochloride was
added in one portion and the homogeneous mixture was stirred overnight at room
temperature. The mixture was concentrated under reduced pressure. The residue was
dissolved in ethyl acetate and this solution was washed with either IN hydrochloric
acid followed by saturated brine, or by saturated brine alone. The ethyl acetate
solution was then dried over anhydrous sodium sulfate, filtered and concentrated under
reduced pressure to yield the desired oxime, 247.
METHOD B
By the general procedure of R.K. Howe, et al J. Heterocvclic Chem.. 1982,19,
721-726 the aldehyde starting material 245 and a molar equivalent amount of
hydroxylamine hydrochloride were dissolved in 30% aqueous methanol and stirred at
10-20 °C for lh. The solution was cooled to 0 °C for lh whereupon the solid oxime
(not illustrated) precipitated. The solid oxime was then isolated by filtration followed
by air-drying.
METHOD C
By the general procedure of R.K. Howe, et al, J. Ore. Chem.. 1980,45,3916-
3918 the aldehyde starting material 245 in 1:1 ethanol-water was treated with 1.1
equivalents of hydroxylamine hydrochloride and 2.5 equivalents of aqueous sodium
hydroxide with cooling. The mixture was then stirred at room temperature for lh.
The reaction mixture was extracted with ether, which was discarded and the aqueous
layer was separated and acidified to pH 6 with concentrated hydrochloric acid with
cooling. The aqueous layer was extracted with ether and the ether layers were
separated. The combined ether layers were dried over anhydrous sodium sulfate,
filtered and concentrated under reduced pressure to yield the desired solid oximes.
a-Chlorooxime Formation (Step 2 of FIG. 3A; Compound 247)
METHODD
Again referring to FIG. 3A, the general procedure described by R.K. Howe, et
al, J. Ore. Chem.. 1980,45,3916-3918 was followed. The oxime was dissolved in
DMF and 0.1 molar equivalent of N-chlorosuccinimide was added and the mixture
was heated to SO °C to initiate the reaction. The remaining 0.9 molar equivalent of N-
chlorosuccinimidc was added in small portions keeping the reaction temperature under
SO °C. After the addition was completed, the mixture was stirred for 0.5h and men
diluted with water. The mixture was extracted with ether and the combined ether
extracts were washed with water and brine. The ether layer was dried over anhydrous
sodium sulfate, filtered and concentrated under reduced pressure to yield the desired a-
chlorooxime 247.
METHOD E
The general procedure described by R.K. Howe, et al, J. Ore. Chem.. 1980,45,
3916-3918 was followed. The oxime was dissolved in DMF and 0.1 molar equivalent
of N-chlorosuccinimide was added and the mixture was heated to 50 °C to initiate the
reaction. The remaining 0.9 molar equivalent of N-chlorosuccinimide was added in
small portions keeping the reaction temperature under 50 °C. After the addition was
complete the mixture was stirred for 3h at room temperature. The resulting DMF
solution containing the desired a-chlorooxime 247 was used immediately in the next
step.
General Procedures for the Preparation of 2-Halo- or 2,2-Dihalo-N-(3- .
ethynylphenyl) Acetamides (FIG. 7A & 7B)
Method F (FIG. 7A)
Step J. Acetylenic cross-coupling reactions
Referring to FIG. 7A, the appropriately substituted m-
bromonitrobenzene 315 or substituted m-iodonitrobenzene was dissolved in a suitable
solvent such as p-dioxane or THF and then treated with at least five molar equivalents
of a suitable amine base, which could be triethylamine, diethylamme or
diisopropylethylamine. Alternatively, the amine base alone could be used as the
solvent A stream of argon gas was men bubbled through the solution for several
minutes, followed by the addition of dichlorobis(triphenylphosphine) palladium (II)
(3-4 mole percent), Cul (6-8 mole percent) and finally trimethylsilylacetylene (1.2-1.3
molar equivalents). The reaction mixture was then heated at 50-80 °C until the
reaction was complete, as monitored by TLC or LC-MS. When the more reactive
substituted m-iodonitrobenzenes were used, the acetylenic cross-coupling reaction
could be performed at room temperature. If the reaction appeared sluggish, additional
trimethylsilylacetylene was added. This general procedure is known in the literature
as the Sonogashira coupling (K. Sonogashira et al., Tetrahedron Lett. 1975,4467).
The reaction mixture was then diluted with ethyl acetate and this solution was washed
several times with brine. Alternatively, the crude reaction mixture was filtered over a
pad of Celite, then diluted with ethyl acetate and washed with brine. The organic layer
so obtained was dried over anhydrous sodium sulfate, filtered and concentrated to
dryness under reduced pressure. The residue was purified by column chromatography
on silica gel, eluting with mixtures of ethyl acetate and hexanes to give the desired
substituted m-(trimethylsilylethynyl) nitrobenzenes 317.
Step 2. Redaction of the nitro group to amines
The substituted m-(trimethylsilylethynyl) nitrobenzene 317 prepared in
Step 1 was dissolved in a mixture of 10-15 volume percent of concentrated
hydrochloric acid in methanol. Then, iron powder (Aldrich Chemical Co.) (5-10
molar equivalents) was added and the mixture was heated at 70-80 °C for 3-4L This
reaction can be highly exothermic when performed on a large scale. After cooling to
room temperature, the reaction mixture was filtered over Celite and the filtrate was
concentrated under reduced pressure. The residue was dissolved in ethyl acetate and
then carefully washed with either aqueous sodium hydroxide or aqueous sodium'
bicarbonate solution. The aqueous layer was discarded and the organic layer was
washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to
dryness under reduced pressure. If necessary the crude product could be purified by
column chromatography on silica gel, eluting with mixtures of hexanes and ethyl
acetate to give the desired substituted m-(trimethylsilylethynyl) anilines 319.
Step 3. Removal of the trimethylsilyl group from the acetylenes
The substituted m-(trimethylsilylethynyl) aniline 319 prepared in Step 2
was dissolved in methanol containing 2-5% water. If the solubility of the aniline in
methanol was poor, an appropriate amount of tetrahydrofuran (THF) was used as a co-
solvent Then anhydrous potassium carbonate (1 molar equivalent) was added and the
mixture was stirred at room temperature for l-24h until the reaction was complete by
TLC analysis. The reaction mixture was concentrated under reduced pressure and the
residue was dissolved in ethyl acetate and washed with brine. The organic layer was
dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure.
The substituted m-aminophenylacetylenes 321 could be purified by column
chromatography on silica gel, eliding with hexanes and ethyl acetate, if necessary.
Step 4. Introduction of the haloacetunide or dihaloacetamide side
chains
The substituted m-aminophenylacetylene 321 prepared in Step 3 was
dissolved in dichloromethane. Triethylamine (1.3 molar equivalents) was added and
the solution was cooled in an ice-bath under nitrogen. Then a solution of acetylating
reagent LG-C(O)-R12 (e.g, haloacetyl chloride or dihaloacetyl chloride; 1.0 molar
equivalent) in dichloromethane was added dropwise. After the addition was complete,
the reaction was allowed to stir 0.5-lh at 0 °C and then allowed to warm to room
temperature. After a total of l-4h reaction time the reaction mixture was diluted with
water. The organic layer was separated and further washed with saturated aqueous
sodium bicarbonate solution and brine. The organic layer was dried over anhydrous
sodium sulfate, filtered and concentrated under reduced pressure to give the
substituted acetamide compound 323.
Alternatively, the substituted m-aminophenylacetylene 321 starting material
was dissolved in dichloromethane and treated successively with l-(3-
ddmethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1 molar equivalent), a
compound of the formula RI2-C(O)OH (e.g., a halo- or dihaloacetic acid;l molar
equivalent) and finally triethylamine (1 molar equivalent). The reaction mixture was
then stirred at room temperature until the substituted m-aminophenylacetylene starting
material 321 was consumed as determined by TLC analysis. The mixture was washed
with water and the organic layer was dried over anhydrous sodium sulfate, filtered and
concentrated to dryness under reduced pressure to give the acetamide 323.
Method G (FIG. 7B)
Referring to FIG. 7B, an appropriately substituted m-iodoaniline or m-
bromoaniline starting material 325 was coupled with trimethylsilyiacetylene as
described in Step 1 of Method F. The resulting substituted m-(trimethybilylethynyl)
aniline 327 was then deprotected using the procedure described in Step 3 of Method F
to give the substituted m-aminophenylacetylene 329 which was then converted to the
desired acetamide 331 as described in Step 4 of Method F.
1,3-Dipolar Cycloaddition Reactions to make Isoxazoles (FIG. 3A; 247 — 211)
Method H
Referring again to FIG. 3A, the o-chlorooxime 247 and 1.0 molar equivalent of
the appropriate phcnylacctylcne were dissolved in either anhydrous THF or DMF and
1.3 molar equivalents of triethylamine was added. The a-chlorooxime immediately
reacted with triethylamine to produce the corresponding phenyl nitrile oxide
intermediate (248a or 248b) and also produced a precipitate of triethylamine
hydrochloride. The heterogeneous mixture was then heated at 70-80 °C for 3-6h to
induce the 1,3-dipolar Cycloaddition reaction of the phenyl nitrile oxide with the
phenylacetylene 249. The solvent was removed by concentration under reduced
pressure. The residue was dissolved in ethyl acetate and this solution was washed with
aqueous sodium bicarbonate solution followed by water and brine. The ethyl acetate
layers were dried over anhydrous sodium sulfate, filtered and concentrated under
reduced pressure to yield the crude product 211. This material was further purified by
column chromatography on silica gel, eluting with hexanes-ethyl acetate or by HPLC
chromatography on a C-18 reversed phase column (mobile phase acetonitrile-water-
trifiuoroacetic acid). The isolated isoxazoles 211 were either crystallized or
characterized as solids by spectral analysis.
In the same manner, the compounds listed below were made from the
corresponding a-chlorooximes and the corresponding phenylacetylenes (the structures
of the compounds are provided in TABLE 1).
Compound 1: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]-6-
fluorophenyl] Acetamide; MW=434 confirmed by LC-MS, tr=37.75 min (Method W)
MH+=433-437
Compound 3: 2,2-Dichloro-N-[3-[3-(2,3-dichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=412 confirmed by LC-MS, tr=38.96 min (Method W) MH+=411-
415
Compound 5: 2,2-Dichloro-N-[3-[5-(2)6-dichlorophenyl)-3-isoxazolyl]phenyl]
Acetamide; MW=416 confinned by LC-MS, tr=37.92 min (Method W) MH+=415-
419
Compound 7:2,2-Dichloro-N-[3-[3-[2-chloro-6-(N-morpholmo)phenyl]-5-
isoxazolyl]phenyl] Acetamide; MW=462 confinned by LC-MS, 1-35.50 min
(Method W) MH+=461-465
Compound 9: 2,2-Dichloro-N-[3-[3-(2,6-dichloropheaiyl)-5-isoxazolyl]phenyl]
Acetamide; MW=416 confinned by LC-MS, 1=36.90 min (Method W) MH+=415-
419
Compound 11: 2,2-Dichloro-N-[3-[3-(2-fluoro-6-thiomethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=411 confinned by LC-MS, tr=35.96 min
(Method W) MH+=410-414
Compound 13: 2,2-Dichloro-N-[3-[3-(2,6-Dichlorophenyl)-5-isoxazolyl]-4-
fluorophenyl] Acetamide; MW=434 confinned by LC-MS, tr=38.82 min (Method W)
Compound 15: 2r2-Dichloro-N-[3-[3-(2-chloro-6-fluoro-3-methylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=414 confinned by LC-MS, tr=28.91 min
(Method X) MH+=413-417
Compound 21: 2,2-Dichloro-N-[3-[3-[2-fluoro-(6-N-morpholinosulfamoyl)phenyl]-
5-isoxazolyl]-phenyl] Acetamide; MW=514 confirmed by LC-MS, tr=32.30 min
(Method W) MH+=513-517
Compound 23: 2,2-Dichloro-N-[3-[3-[2,6-dimethyl-4-(N-morpholino-2-
emyleneoxy)phenyl]-5-isoxazolyl]pheny]] Acctamide; MW=543 confirmed by LC-
MS, tr=27.59 min (Method X) MHV542-546
Compound 25: 22-Dichloro-N-[3-[3-(2,6-dicMorophenyl)-5-(l,2,4-
oxadiazolyl)]phenyl] Acetamide; MW=417 confirmed by LC-MS, tr=20.70 min
(Method X) MH+=416-420
Compound 27: 2,2-Dichloro-N-[3-[3-(2-chloro-6-fluorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=400 confirmed by LC-MS, tr=35.94 min (Method W) MH+=399-
403
Compound 29: 2,2-Dibtomo-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=505 confirmed by LC-MS, tr=33.30 min (Method W) MH+=503-
507
Compound 31: 2,22-Dichloro-N-[3-[3-(2-chloro-6-methylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=396 confirmed by LC-MS, tr=33.26 min
(Method W) MH+=393-397
Compound 33: 2,2-Dichloro-N-[3-[3-(2-trifluoromethylpbeny])-5-isoxazolyl]phenyl]
Acetamide; MW=415 confirmed by LC-MS, tr=32.10 min (Method W) MH+=414-
418
Compound 35: 2,2-Dichloro-N-[3-[3-(2-hydroxy-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=431 confirmed by LC-MS, tr=l 3.80 min
(Method Y) MH+=430-434
Compound 37: 2,2-Dichloro-N-[3-[3-[2-(N-morpholino)-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=500 confirmed by LC-MS, 1=36.23 min
(Method W) MHf=499-503
Compound 39: 2,2-Dichloro-N-[3-[3-(2-chloro-6-isopropylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=424 confirmed by LC-MS, V=21.72 min
(Method X) MH+=423-427
Compound 41: 2,2-Dichloro-N-[3-[3-(2-fluoro-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=433 confirmed by LC-MS, tr=21.05 min
(Method Y) MH+=432-436
Compound 43: 2,2-Dichloro-N-[3-[3-(2-fluoro-6-methoxyphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=395 confinned by LC-MS, tr=34.73 min
(Method W) MH+=494-498
Compound 45: 2,2-Dichloro-N-[3-[3-(2-difluoromethoxyphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=413 confinned by LC-MS, 1=7.48 min (Method
Z)MH+=412-416
Compound 47: 2,2-Dichloro-N-[3-[3-(2,6-dimethyhl]phenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=375 confinned by LC-MS, Tr=20.69 min (Method X) MH+=373-378
Compound 49: 2,2-Dichloro-N-[3-[3-(2-fluoro-6-iodophenyl)-5-isoxa2olyl]phenyl]
Acetamide; MW=491 confirmed by LC-MS, tr=37.19 min (Method W)MH+=490-494
Compound 51: 2,2-Dichloro-N-[3-[3-(6-chloro-2-fluoro-3-methy]phenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=414 confinned by LC-MS, tr=38.16 min
(Method W)MH+=413-417
Compound 53: 2,2-Dichlcro-N-[3-[3-(2-chloro-3,6-difluorophenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=418 confinned by LC-MS, tr=21-25 min
(Method Y) MH+=417-421
Compound 57: 2,2-Dichloro-N-f3-[3-(2,6-dchlorophenyl)5-isoxazoiylphenyl]-N-
methyl Acetamide; MW=430 confinned by LC-MS,tr=20.70 min (Method X)
MH+=429-433
Compound 61: 2,2-Dichloro-N-[3-[3-(2-ethoxyphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=391 confinned by LC-MS, tr-=7.66 min (Method X) MH+=390-394
Compound 63: 2,2-Dichloro-N-[3-[3-(2-isopropylphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=389 confirmed by LC-MS, tr=35.37 min (Method W) MH+=388-
392
Compound 65: 2,2-Dichloro-N-[3-[3-(2,6-dichloro-4-dimethylaminophenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=496 confirmed by LC-MS, tr=40.10 min
(Method W) MH+=495-499
Compound 67: 2-Chloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=382 confirmed by LC-MS, tr=34.27 min (Method W) MH+=379-
383
Compound 69: 2,2-Dichloro-N-[3-[3-(2,4,6-trimethylphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=389 confirmed by LC-MS, tr=38.76 min (Method W) MH+=388-
392
Compound 73: 2,2-Dichloro-N-[3-[3-[2,6-dichloro-4-(N-
morpholinopropyleneoxy)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=559
confirmed by LC-MS, tr-27.30 min (Method W) MH+=558-562
Compound 75: 2,2-Dichloro-N-[3-[3-[2,6-dichloro)-4-(N-
morpholinoethyleneoxy)phenyl]-S-isoxazolyl]-pheny]] Acetamide; MW=545
confirmed by LC-MS, tr=26.10 min (Method W) MH+=544-548
Compound 77: 2,2-Dichloro-N-[3-[3-(2-methoxy-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=445 confirmed by LC-MS, tr=35.02 min
(Method W) MH+=444-448
Compound 79: 2,2-Dichloro-N-[3-[3-(2-chloro-6-cyclopropylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=422 confirmed by LC-MS, tr=38.28 min
(Method W) MH+=421-425
Compound 81: 2,2-Dichloro-N-[3-[3-(2-chloro-6-methoxyphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=412 confirmed by LC-MS, tr=34.75 min
(Method W) MH+=411-415
Compound 83: 2,2-Dichloro-N-[3-[3-(2-chloro-6-hydroxyphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=398 confirmed by LC-MS, tr=18.04 min
(Method X) MH+=397-401
Compound 85: 2,2-Dichloro-N-[3-[3-(2-methyl-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=429 confirmed by LC-MS, tr=18.83 min
(Method X) MH+=428-432
Compound 87: 2,2-Dichloro-N-[3-[5-(2,6-dichlorophenyl)-3-(l,2,4-
oxadiazolyl)]phenyl] Acetamide; MW=417 confirmed by LC-MS, tr= 18.30 min
(Method X) MH++Na=439-443
Compound 89: 2,2-Dichloro-N-[3-[3-(2-cyclopropyl-6-trifluoromemylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=455 confirmed by LC-MS, tr=19.45 min
(Method X) MH+=454-458
Compound 91: 2,2-Dichloro-N-[3-[3-(2-methoxy-6-methylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=391 confirmed by LC-MS, tr=34.99 min
(Method W) MH+=390-394
Compound 93: 2>Dichloro-N-[3-[3-(2-isopropyl-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=457 confirmed by LC-MS, tr=18.11 min
(Method X) MH+=456-460
Compound 95: 2,2-Dichloro-N-[3-[3-[2-chloro-6-(N-morpholino-2-
ethyleneoxy)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=511 confirmed by LC-
MS, tr=10.49 min (Method Y) MH+=5l0-514
Compound 97: 2,2-Dichloro-N-[3-[3-(2-chloro-6-cyclopentylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=450 confirmed by LC-MS, tr=22.35 min
(Method X) MH+=449-453
Compound 99: 2,2-Dichloro-N-[3-[3-[2-chloro-6-(4-methylpiperazino)phenyl]-5-
isoxazolyl]phenyl] Acetamide; MW=480 confirmed by LC-MS, tr=25.83 min
(Method W) MH+=479-483
Compound 101: 2-Iodo-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=473 confirmed by LC-MS, tr=35.62 min (Method W) MH+=472-
476
Compound 103: 2,2-Dichloro-N-[3-[3-(2-chloro-6-n-butylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=438 confirmedby LC-MS, tr=22.15 min
(Method X) MH+=437-441
Compound 105: 2,2-Dichloro-N-[3-[3-{2-cyclopentyl-6-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=383 confirmed by LC-MS, tr=37.74 min
(Method W) MH+=382-386
Compound 107: 2,2-Dichloro-N-[3-[3-(2,6-dichloro)phenyl)-5-isoxazolyl]-4-(N-
morpholinosulfamoyl)-phenyl] Acetamide; MW=565 confirmed by LC-MS, tr=32.23
min (Method W) MH+=564-568
Compound 109: 2,2-Dichloro-N-[3-[3-[2-trifluoromethyl-6-(4-
methylpiperazino)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW-513 confirmed by
LC-MS, W6.18 min (Method W) MH+=512-516
Compound 111: 2,2-Dichloro-N-[3-[3-(2-chloro-6-cyclohexylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=464 confirmed by LC-MS, tr=22.70 min
(Method W) MH+=463-467
Compound 113: 2,2-Dichloro-N-[3-[3-(2-trifluorometb.oxyphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=431 confirmed by LC-MS, tr=34.26 min
(Method W) MHf=430-434
Compound 115: 2,2-Dichloro-N-[3-[3-(2-carbomethoxy)phenyl-5-isoxazolyl]phenyl]
Acetamide; MW=405 confirmed by LC-MS, tr=7.08 min (method z) MH+=4O4-408
Compound 117: 2-Dichloro-N-[3-[3-[2-chloro-6-(N-imidazolyl)phenyl]-5-
isoxazolyl]phenyl] Acetamide; MW=448 confirmed by LC-MS, tr=24.72 min
(Method W) MH+=447-451
Compound 119: 2,2-Dichloro-N-[3-[3-(2-isopropyloxyphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=4O5 confirmed by LC-MS, tr-=34.78 min (Method W) MH+=404-
408
Compound 121: 2, 2-Dichoro-N-[3-[3-(2,6-diisopropylphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=431 confirmed by LC-MS, tr=22.32 min (Method X) MH+=430-434
Compound 123: 2,2-Dichloro-N-[3-[3-(2-phenyl)phenyl-5-isoxazolyl]pheayl]
Acetamide; MW=424 confirmed by LC-MS, tr=21.48 min (Method X) MH+=423-427
Compound 125: 2,2-Dichloro-N-[3-[3-[2,6-dichloro-4-(N-piperidinylethylenoxy)
phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=543 confirmed by LC-MS, tr=27.59
min (Method W) MH+=542-546
Compound 127: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]-4-
methoxyphenyl] Acetamide; MW=446 confirmed by LC-MS, tr=36.71 min (Method
W)MH+=445-449
Compound 129: 2,2-Dichloro-N-[3-[3-(2-cyclopentylphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=415 confirmed by LC-MS, tr=22.24.min (Method X) MH+=414-418
Compound 131: 2-Dichloro-N-[3-[3-[2,2-chloro-6-(N,N--dimethylethylene-N'-
methylamino)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=482 confirmed by LC-
MS, tr=26.06 min (Method W) MH+=481-485
Compound 132: (±)-2,2-Dichloro-N-[3-[3-[2-chloro-6-(3-dimemylamino-N-
pyrrolidino)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=494 confirmed by LC-
MS, tr=30.00 min (Method W) MH+=493-497
Compound 135: 2,2-Dichloro-N-[3-[3-(3-carbomethoxy-2,6-dichlorophenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=474 confirmed by LC-MS, 1=35.61 min
(Method W) MH+=473-477
Compound 137: 2,2-Dichloro-N-[3-[3-(2,3,6-trichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=451 confirmed by LC-MS, tr=28.75 min (Method X) MH+=450-454
Compound 139: 2,21-Dichloro-N-[3-[3-(3-carboxy-2,6-dichloropbenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=460 confirmed by LC-MS, tr=31.46 min
(Method W) MH+=459-463
Compound 141: 2,2-Dichloro-N-[3-[3-(2-chloro-5-trifluoromethylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW-450 confirmed by LC-MS, tr=22.11 min
(Method X) MH+=449-453
Compound 143: 2,2-Dichloro-N-[3-[3-[2,4-dichloro-6-(N-morpholino-2-
ethyleneoxy)phenyl]-5-isoxazolyl]-phenyl] Acetamide; MW=545 confirmed by LC-
MS, tr=28.25 min (Method X) MH+=544-548
Compound 145: 2,2-Difluoro-N-[3-[3-(2,6-dicfalorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=383 confirmed by LC-MS, tr=35.58 min (Method W) MH+=382-
386
Compound 149: 2,2-Dichloro-N-[3-[3-(2,6-difluoro-3-methylphenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=397 confirmed by LC-MS, tr=37.13 min
(Method W) MH+=396-400
Compound 151: 2,2-Dichloro-N-[3-[3-[2-chloro-6-(4-
carboethoxypiperidino)phcnyl]-5-isoxazolyl]-phenyl] Acetamide; MW=537 confirmed
by LC-MS, tr=39.98 min (Method W) MH+=S36-540
Compound 153: 2,2-Dichloro-N-[3-[3-(2-fluoro-6-methylsulfonyl)phenyl-5-
isoxazolyl]phenyl] Acetamide; MW=443 confirmed by LC-MS, tr=6.62 min (method
z)MH+=M41-445
Compound 155: 2,2-DichIoro-N-[3-[3-[2-(N-morpholinomethyl)phenyl]-S-
isoxazolyl]phenyl] Acetamide; MW=446 confirmed by LC-MS, tr=23.63 min
(Method W) MH+=445-449
Compound 157: 2,2-Dichloro-N-[3-[3-(2-carboxyphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=391 confirmed by LC-MS, tr=6.40 min (Method Z) MH+=390-394
Compound 159: 2,2-Dichloro-N-[3-[3-(2,4-dichlorophenyl)-5-isoxazolyl]phenyl]
Acetamide
Compound 161: 2,2-Dichloro-N-[3-[3-(2-benzyloxyphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=453 confirmed by LC-MS, tr=39.69 min (Method W) MH+=452-
456
Compound 163: 2,2-Dichloro-N-[3-[3-(2,3-dimethylphenyl)-5-isoxazo]yl]phenyl]
Acetamide; MW=375 confirmed by LC-MS, tr=37.62 min (Method W) MH+=374-
378
Compound 165: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]-6-
methylphenyl] Acetamide; MW=430 confirmed by LC-MS, tr=36.48 min (Method
W)MH+=429-433
Compound 167: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]-2-
methylphenyl] Acetamide; MW=430 confirmed by LC-MS, tr=35.85 min (Method
W)MH+=429-433
Compound 169: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl][6-(N-
morpholino)phenyl] Acetamide; MW=501 confirmed by LC-MS, tr=39.10 min
(Method W) MH+=500-504
Compound 171: 2,2-Dichloro-N-[3-[3-(2,6-Dichlorophenyl)-5-isoxazolyl]-6-(N-
morpholino-2-ethyleneoxy)phenyl] Acetamide; MW=545 confirmed by LC-MS,
tr=27.77 min (Method W) MH+=544-548
Compound 173: 2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-isoxazolyl]-6-
metboxyphenyl] Acetamide; MW=446 confirmed by LC-MS, tr=20.80 min (Method
X)MH+=445-449
Compound 175: 2,2-Dichloro-N-[3-[3-[2-chloro-6-[4-(N-piperidinyl)-N-
piperidinyl]phenyl]-5-isoxazolyl]phenyl] Acetamide; MW=548 confirmed by LC-MS,
tr=27.95 min (Method W) MH+=547-551
Compound 177: 2,2-Dichloro-N-[3-[3-(2-chlorophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=382 confirmed by LC-MS, 1,-15.45 min (Method Y) MH+=381-385
Compound 179: 2,2-Dichloro-N-[3-[3-(2-bromophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=426 confirmed by LC-MS, tr=15.59 min (Method Y) MH+=425-429
Compound 181: 2,2-Dichloro-N-[3-[3-(2-chloro-6-nitrophenyl)-5-isoxazolyl]phenyl]
Acetamide; MW-426 confirmed by LC-MS, tr=14.47 min (Method Y) MH+=425-429
Compound 183: 2,2-Dichloro-N-[3-[3-(2-methoxyphenyl)-5-isoxazolyl]phenyl]
Acetamide; MW=377 confirmed by LC-MS, tr=14.90 min (Method Y) MH+=376-380
Compound 185: 2,2-Dichloro-N-[3-[3-(2-bromo-6-chlorophenyl)-5-
isoxazolyl]phenyl] Acetamide; MW=461 confirmed by LC-MS, tr=15.58 min
(Method Y) MH+=460-464
Compound 187: 2,2-Dichloro-N-[3-[3-(2-chloro-6-(4-amino-N-piperidinyl)phenyl]-
5-isoxazolyl] phenyl] Acetamide; MW=480 confirmed by LC-MS, tr=10.90 min
(Method Y) MH+=479-483
Preparation of 1,2,4-Oxadiazoles
2,2-Dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-(l,2,4oxadlazolyl)]phenyl]
Acetamide (Compound 25)
Step l
2,6-Dichlorobenzamidoxime (1.0g) was dissolved in pyridine and m-
nitiobenzoyl chloride (0.91gm, 1.0 molar equivalent) was added. The solution was
stirred at room temperature for lh under nitrogen, then heated at 90 °C for 4h. The
solution was cooled to room temperature, and poured into ice water. The pH of the
solution was adjusted to approximately pH 10 with 2M aqueous sodium carbonate
solution. The mixture was extracted with ether and the organic layer was dried over
anhydrous sodium sulfate, filtered and concentrated under reduced pressure to dryness.
The residue was dissolved in ethyl acetate. Addition of hexanes to the solution gave
3-(2,6-dichlorophenyl)-5-(3-nitrophenyl)-l,2,4-oxadiazole as a white solid (0.69g).
NMR (300 MHz, DMSO-d6): 8.52 (s, 1H), 8.38 (d, 1H), 8.18 (d, 1H), 7.78 (t, 1H),
7.57 ppm (m, 3H). LC-MS tr =38.2 min (Method W) MH++NA = 359
Step 2
The nitro oxadiazole prepared in Step 1 (200mg) was dissolved in ethyl acetate
(20mL) and tin (II) chloride dihydrate (162 mg, 1.2 molar equivalent) was added. The
mixture was stirred at room temperature for lh. An additional 1.2 molar equivalents
of tin (II) chloride was added. After a further 4h at room temperature, the reaction
mixture was diluted with ethyl acetate and washed three times with water. The
organic layer was dried over anhydrous sodium sulfate, filtered and concentrated
under reduced pressure to give the desired 3-(2,6-dichlorophenyl)-5-(3-aminophenyl)-
1,2,4-oxadiazole as a white solid in quantitative yield. NMR (300 MHz, DMSO-d6):
7.70 (m, 3H), 7.36 (s, 1H), 7.24 (d, 2H), 6.91 (m, 1H), 5.57 ppm (broad s, 2H). LC-
MS ttr=33.1 min (Method W) MH+ = 307
Step 3
The aminophenyl oxadiazole prepared in Step 2 (200mg) was dissolved in 5
mL of dichloromethane, triethylamine (90 µL, 1.0 molar equivalent) was added, and
the mixture was cooled in an ice-bath under nitrogen. Then dichloroacetyl chloride
(65|iL, 1.0 molar equivalent) was added and the mixture was allowed to stir for 2h at 0
°C. The solution was diluted with dichloromethane and men washed with saturated
aqueous sodium bicarbonate followed by brine. The organic layer was dried over
anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give a
brown oil. Purification by column chromatography on silica gel, eluting with 8:1
hexanes-ethyl acetate, gave a colorless oil. Trituration of the oil with hexanes-ethyl
acetate gave the title compound, 2,2-dichloro-N-[3-[3-(2,6-dichlorophenyl)-5-(l,2,4-
oxadiazolyl)]phenyl] acetamide, as a white solid (70 mg). NMR (300 MHz, CDC13):
8.34 (m, 2H), 8.05 (d, 1H), 8.00 (d, 1H), 7.59 (t, 1H), 7.44 (m, 3H), 6.09 ppm (s, 1H).
LC-MS tr =20.71 min (Method X) MH+ = 418
Preparation of Pyrazoles
2,2DlchIoro-N-[3-[3-(2,6-dichlorphenyI)-5-(pyrazolyl)] phenyl] Acetamide
(Compound 189)
Stepl
To a stirred solution of lithium bis(trimethylsilyl)amide (1.0 molar in
tetrahydrofuran, 1 1mL, 1.1 mole equivalent) cooled at -70 under nitrogen was added
dropwise a solution of 2,6 dichloroacetophenone ( 965 mg, 1.0 molar equivalent) in
anhydrous tetrahydrofuran. The resulting mixture was stirred at -20 °C for 2 h. The
reaction mixture was re-cooled to -70 °C, and a solution of 3-nitrobenzoylcyanide
(900mg, 1.0 molar equivalent) in tetrahydrofuran was added dropwise. The 3-
mtrobenzoylcyanide was prepared according to the procedures of S.Yamaguchi et al.
in, Bull. Chem. Soc. Jpn. 1989,62,3036-3037. The mixture was allowed to warm to
room temp over lh and was stirred at room temperature for 2h. The reaction was
quenched by the addition of saturated aqueous ammonium chloride. The reaction
mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous
sodium sulfatc, filtered, and concentrated under reduced pressure to dryness. The
crude solid product was purified by column chromatography over silica gel using
hexanes and ethyl acetate to give the desired l-(2,6-dichlorophenyl)-3-(3-nitrophenyl)-
1,3 propanedione. NMR 300MHz (CDCl3) 8.75 (m, 1H), 8.40 (m, 1H), 8.28 (m,
1H), 7.69 (t, 1H), 7.39 (m, 2H), 6.43 (s, 2H)
Step 2
The diketone prepared in Step 1 (100mg) was dissolved in ethanol. To this
solution was added hydrazine monohydrate (5 molar equivalents) and 1 drop of
concentrated hydrochloric acid. The mixture was then heated at 80-90 °C overnight
The solvent was removed under reduced pressure. The residue was dissolved in ethyl
acetate and washed with saturated sodium bicarbonate solution. The organic layer was
dried over anhydrous sodium sulfate, filtered, and concentrated under reduced
pressure to give the desired pyrazole as a white solid (57 tag). NMR (300 MHz,
CDCl3): 8.69 (t, 1H), 8.22 (m, 2H), 7.62 (t, 1H), 7.44 (d, 2H), 7.33 (m, 1H), 6.86 ppm
(s, 1H).
LC-MS tr = 14.53 min (Method Y) MH+ = 333-337
Step 3
The 3-(2,6-dichlorophenyl)-5-(3-nitrophenyl) pyrazole prepared in Step 2
(57mg) was dissolved in 50% aqueous ethanol and treated with iron powder (57 mg, 6
molar equivalents), and ammonium chloride (18.2 mg, 2 molar equivalents). The
mixture was heated at 70-80°C for 4h. The reaction mixture was cooled to room
temperature then filtered and the filtrate-was concentrated to dryness under reduced
pressure. The residue was dissolved in ethyl acetate and washed with water and brine.
The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated
under reduced pressure to give 3-(2,6-dichlorophenyl)-5tr3-aminophenyl)pvrazole as a
white solid (27mg). NMR (300 MHz, CDC13): 7.40 (d, 2H), 7.25 (t, 1H), 7.20 (m,
1H), 7.11 (m, 2H), 6.68 ppm (m, 2H). LC-MS tr = 5.66 min (Method Z) MH+ = 303-
307
Step 4
Dichloroacetic acid (13 mg, 1.1 molar equivalents), O- (7-azabenzotriazol-1-
yl)-N,N,N',N'- tetramethyluronium hexafluorophosphate (HATU) (38mg, 1.1 molar
equivalent), and N-methylmorpholine(22µL, 2.2 molar equivalents) were dissolved in
anhydrous dichloromethane and stirred for 5 minutes. Then the 3-(2,6-
dichlorophenyl)-5-(3-aminophenyl)pyrazole prepared in Step 3 was added, and the
mixture stirred at room temperature overnight. The reaction mixture was diluted with
ethyl acetate and washed with 1M aqueous hydrochloric acid, saturated sodium
bicarbonate solution, then brine. The organic layer was dried over anhydrous sodium
sulfate, filtered, and concentrated under reduced pressure. The crude product was
purified by column chromatagraphy eluting with 25% ethyl acetate in hexanes to give
2,2-DichloitrN-[3-[3 white solid. NMR (300 MHz, CDC13): 8.40 (broad s, 1H), 8.00 (broad s, 1H), 7.62 (t,
2H), 7.43 (m, 3H), 7.30 (m, 2H), 6.78 (broad s, 1H), 6.07 ppm (s, 1H). LC-MS tr =
13.75 min (Method Y) MH+ - 415-419.
7.2 Exemplary Compounds of the Invention Inhibit HCV Translation
Or Replication
7.2.1 Replicon Assay
The inhibitory activity of certain exemplary compounds of the
invention was confirmed using an HCV replicon assay. The HCV replicon can
include such features as the HCV 5' untranslated region including the HCV IRES, the
HCV 3' untranslated region, selected HCV genes encoding HCV polypeptides,
selectable markers, and a reporter gene such as luciferase, GFP, etc. In the assay,
actively dividing 5-2 Luc replicon-comprising cells (obtained from Rolf
Bartenschlager, see Lohmann et al., 1999, Science 285:110-113) were seeded at a
density of between about 5,000 and 7,500 cells/well onto 96 well plates (about 90 (il
of cells per well) and incubated at 37 °C and 5% CO2 for 24 hours. Then, the test
compound (in a volume of about 10 µl) was added to the wells at various
concentrations and the cells were incubated for an additional 24 hours before
luciferase assay. The media was aspirated from each well and Bright-Glo (Promega,
Madison, WI) luciferase assay reagents were added to each well according to the
manufacturer's instructions. Bri0efly, the Bright-Glo reagent was diluted 1:1 with PBS
and 100 µl of diluted reagent was added to each well. After 5 min of incubation at
room temperature, luciferin emission was quantified with a luminometer. In this
assay, the amount of test compound that yielded a 50% reduction in luciferase
emission (IC50) was determined.
7.2.2 Western Blot Assay
Certain exemplary compounds of the invention were also tested
for their ability to inhibit HCV replication using a quantitative Western blot analysis
with antibodies specific for the HCV nonstructural protein NS5A. Actively dividing
9-13 replicon cells were seeded into 6-well plates at a density of 1X105 cells/well in a
volume of 2 ml/well and incubated at 37°C and 5% CO2 for 24 hours. Various
concentrations of test compounds (in a volume of 10 ul) were added to the wells and
the cells incubated for another 48 hours. Protein samples were prepared from the
cultured cells, resolved on a SDS-PAGE gel and transferred to a nitrocellulose
membrane. The membrane was blocked with 5% non-fat milk in PBS for 1 hour at
room temperature. Primary antibody (and NSSA antibody; BIODESIGN
International, Saco, ME) incubation was performed for 1 hour at room temperature,
after which the membrane was washed 3 times (for 15 min per time) with PBST (PBS
plus 0.1% Tween 20). Horseradish peroxidase conjugated secondary antibody
incubation was performed for 1 hour at room temperature and the membrane was
washed 3 times (for 15 min per time) with PBST. The membrane was then soaked in
substrate solution (Pierce) and exposed to a film or quantified using an imager. In this
assay, the amount of test compound that yielded a 50% reduction in the amount of
NSSA protein translated as compared to a control sample (IC50) was determined.
The results of the Replicon and Western blot assays are provided in TABLE 1,
below. In TABLE 1, a value of"+" indicates an IC50 of 10 µM or less in the specified
assay; a value of"-" indicates an IC50 of greater than 10 µM in the specified assay.
Many of the compounds exhibited IC50S in the Replicon assay in the nanomolar range.
7.2.3 Luciferase Counter Screen
A counter screen was used to identify non-specific inhibitors of
the luciferase reporter gene. In the counter screen, a cell line carrying a construct such
as a CMV-driven luciferase gene was used to identify compounds that inhibit the
reporter gene, and not HCV. In these CMV-Luc cells, the DNA construct, which
comprises a luciferase gene downstream of a CMV promoter, is permanently
integrated into the chromosome of Huh7 cells. For the counter screen, actively
dividing CMV-Luc cells were seeded at a density of 5000-7500 cells/well in a volume
of 90 µl/well into 96 well plate(s). The cells were then incubated at 37°C and 5% CO2
for 24 hours. Various concentrations of test compounds (in a volume of 10 ul) were
added to the wells and the cells were incubated for another 24 hours. Media was
aspirated from each well and Bright-Glo (Pharmacia) luciferase assay reagents were
added to each well according to the manufacturer's manual. Luciferin counts were
taken using a luminometer. IC50 values were greater than 10 µM in the counter screen
luciferase inhibition assay for the compounds of TABLE 1 that were tested.
7.2.4 PCR Assay
A TaqMan RT-PCR assay (Roche Molecular Systems,
Pleasanton, CA) was used to analyze HCV RNA copy numbers, which confirmed mat
the viral genome of HCV is not being replicated. Actively dividing 9-13 replicon cells
were seeded at a density of 3 x 104 cells/well in a volume of 1 ml/well into 24-well
plates. The cells were then incubated at 37° C and 5% CO2 for 24 hours. Various
concentrations of test compounds (in a volume of 10 ul) were added to the wells and
the cells were incubated for an additional 24-48 hours. Media was removed by
aspiration and RNA samples prepared from each well. TaqMan one step RT-PCR
(Roche Molecular Systems, Alameda, CA) was performed using the freshly prepared
RNA samples according to the manufacturer's manual and analyzed on an ABI Prism
7700 Sequence Detector (Applied Biosystems). The ratio of HCV RNA to cellular
GAPDH RNA was used as in indication of specificity of HCV inhibition to confirm
that the viral genome was not replicated.
7.2.5 HCV Infection Assay
The activity of Compound 9 was also confirmed in an HCV
infection assay. The assay was carried out essentially as described in Fournier et aL,
1998, J. Gen. Virol. 79:2367-2374. Briefly, hepatocyte cells from a doner were plated
on Day 1. On Day 3, the cells were inoculated with HCV vims and test compound
was added. On Day 5, the medium was changed and test compound was added. On
Day 7, the medium was changed and test compound was added. On Day 8, the RNA
was isolated and the HCV RNA quantified using a Taqman assay. Compound 9
exhibited an IC50 of less than 10 [iM in this assay.
7.3 The Compounds Are Non-Toxic In Cellular and Animal Models
7.3.1 Cytotoxicity
Compounds 67,167,169,13,1, 145, 19,119,63,31,39,103,
123,121,97,129,79, 111, 85,89,109,127,131,95,47,57,69,165,161,163,3,137,
15,141, 41, 53,33,113, 93,105,77,91,81,83, 35,27, 65,7,135,51,139,51,49,
143,5,149,11,37,21,45,61,75,23,125,73,43,171 and 101 were tested in a
cytotoxidty assay with liver cells including an HCV replicon (5-2 Luc cells, 9-13 cells
or Huh-7 cells). In the assay, cells were seeded onto 96-well plates (approx. 7500
cells/well in a volume of 90 µl) and grown for 24 hr at 37°C. On day 2, various
concentrations of test compound (in a volume of 10 µl) were added to the wells and
the cells were grown for an additional 24 hr at 37°C. On day 3, an ATP-dependent R-
Luciferase assay (Cell Titer Glo assay) was performed to determine the number of
viable cells. With the exception of compounds 67,47,69,105,27 and 23, all
compounds tested exhibited an IC50 of greater than 10 µM, confirming that the
compounds are non-toxic. Of the remaining compounds, all but compound 69, which
exhibited an IC50 of 3 µM, had IC50S greater than 5 µM, demonstrating mat these
compounds are well-tolerated, as well.
7.3.2 Animal Stuthes
The safety of compound 9 was evaluated in rats by both
subcutaneous and intravenous administration in several experiments. Doses as high as
30 mg/kg/day were well tolerated. The experiments performed are summarized below.
In a first study the toxicity of compound 9 was evaluated either by the
subcutaneous (SC) route or the intravenous (TV via jugular cannula) route of
administration in Sprague Dawley rats. There were two male rats in each group. A
dose escalation scheme was employed where compound 9 was delivered IV or SC for
3 consecutive days at a dose of 10 mg/kg (study Days 1-3) in a 80%:20% - PEG/water
vehicle; delivered one day IV or SC dose of 30 mg/kg (study Day 4) in 100% PEG;
and an IV dose of 60 mg/kg (study Day 5) in 100% PEG. Compound 9 was well
tolerated at doses up to and including 30 mg/kg by both routes of administration.
However, when the IV dose was increased to 60 mg/kg on Day 5 immediate clinical
signs (collapsing, thrashing, dyspnea and reddish discolored urine) were observed.
The symptoms were transient abating within 1 hour. Toxicokinetic determinations
from the current study and what is known from an earlier experiment demonstrate high
exposure from the IV route and much lower exposure via the subcutaneous route. As
expected by the IV route Cmax is achieved rapidly at about two minutes with a Tl/2
of about 5 minutes with measurable compound 9 still apparent after 2 hours. By the
SC route Tmax is achieved at about 30 minutes and exposure remains sustained
through 2 hours post-dosing.
In a second study compound 9 was administered by the IV route at doses of 10
and 30 mg/kg in 100% PEG. The volume administered for the 10 mg/kg dose was
0.67 ml/kg/day and volume given the 30 mg/kg group was 2 ml/kg/day. In addition,
there were two control groups. One control received 100 % PEG alone at a volume of
2 ml/kg/day while the other was an untreated sham control group. All groups (except
for the untreated control with 3 male rats) had 4 male rats each. Parameters of study
included: clinical observations, body weights, hematology, clinical chemistry, gross
necropsy, organ weights, bone marrow assessment and histopathology of selected
organs. There were very slight decreases in red blood cells, hemoglobin and
hematocrit at 30 mg/kg relative to the untreated control but not the vehicle control.
Otherwise, there were no untoward findings in any other in life parameter, clinical
pathology, bone marrow cytology, gross and/or microscopic morphological changes
attributed to compound 9 observed in the study. A dose of 30 mg/kg was considered
the NOAEL (no observed adverse effect level) by the IV route of administration
during 7 days.
In a third study compound 9 was compared with two other compounds and
administered at a dose of 10 and 30 mg/kg in 100 % PEG and delivered by IV at a
concentration of 1 ml/kg/day first via a jugular cannula and when the cannula failed by
the lateral tail vein. A vehicle control group received the 100% PEG alone at the same
volume. Groups comprised 3 males and 3 females each. Before reducing the dose to
10 and 30 mg/kg two rats received 100 mg/kg IV at a volume of 1 ml/kg. Both
animals thed within a minute or two of dosing acutely from apparent respiratory
failure. Necropsy revealed only mat a drug precipitate had formed at the terminal end
of the cannula. Death may have been associated with an emboli fonned by
precipitated drug. Parameters of study included: clinical observations, body weights,
hematology, clinical chemistry, gross necropsy, organ weights and bistopathology of
selected organs (including injection sites).
Clinical observations, body weights, hematology and clinical chemistry and
organ weights were unaffected by treatment with compound 9 when compared with
the vehicle control. At necropsy there were no gross or microscopic morphological
changes associated with compound 9. There were, nevertheless, changes/lesions
attributed to the irritancy of the 100% PEG vehicle. These changes included those
associated with the injection site focal to the tissues surrounding or in proximity to the
end of the cannula (several terminal ends of the caimulas were obstructed) and in the
tail and/or changes associated with subacute IV administration of several animals in
both the compound 9 and vehicle control group. The NOAEL for intravenous
administration of compound 9 during 14-days was judged to be 30 mg/kg.
7.4 Sustained Plasma Levels Are Achieved
The pharmacokinetic properties of compound 9 were calculated in rats,
monkeys and chimpanzees using the intravenous and subcutaneous routes of
administration with a variety of different delivery vehicles. Sustained plasma levels
were achieved with several different liposome suspension vehicles using subcutaneous
administration: (i) 5 mg/ml compound 9 in water with 100 mg/ml lecithin; (ii) 5 mg/ml
compound 9 in water with 200 mg/ml lecithin; and (iii) 5 mg/ml compound 9 in water
with 100 mg/ml lecithin and 5 mg/ml cholesterol. Based on these results, it is
expected mat other liposome formulations as are well-known in the art may be used to
administer the compounds of the invention
All publications and patent applications cited in this specification are herein
incorporated by reference as if each individual publication or patent application were
specifically and individually indicated to be incorporated by reference.
Although the foregoing invention has been described in some detail by way of
illustration and example for purposes of clarity of understanding, it will be readily
apparent to one of ordinary skill in the art in light of the teachings of this invention
that certain changes and modifications may be made thereto without departing from
the spirit or scope of the appended claims.
WE CLAM-
1. A compound according to structural formula (I):
including the pharmaceuacally acceptable salts, hydrates, solvates,
N-oxides and prodrugs thereof wherein:
X and Y are each, independently of one another, N or O, provided that
X and Y are not both O;
Z is N or -CH-, provided that Z is -CH- when X and Y are both N;
R2, R3, R4, R5, R6, R8, R9, R10 and R13 are each, independently of one another,
selected from the group consisting of hydrogen, -OH, -CH, -CN, -NO2, halo, fluoro,
chloro, bromo, iodo, lower" alkyl, substituted lower alkyl, fqwer heteroalkyl,
substituted lower heteroalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cyclohetcroalkyl 'lower aloalkyl, monohalomethyl, dihalomethyl,
trihalomethyl, trifluoromethy lower alkylthio, substituted lowetralkylthio, lower
alkoxy, substituted lower alkoxy, methoxy, substituted methoxy, lower heteroalkoxy,
substituted lower heteroalkoxy, cycloalkoxy, substituted cycloalkoxy,
cycloheteroalkoxy, substituted cycloheteroalkoxy, lower haloalkoxy,
monohalomethoxy, dihalomethoxy, trihalomethoxy, trifluoromethoxy, amino, lower
di- or monoalkylamino, substituted lower di- or monoalkylamino, aryl, substituted
aryl, aryloxy, substituted aryloxy, phenoxy, substituted phenoxy, arylalkyl, substituted
arylalkyl, arylalkyloxy, sabstituted arylalkyloxy, benzyl, benzyloxy, heteroaryl,
substituted heteroaryl, heteroaryloxy, substituted heteroaryloxy, heteroarylalkyl,
substituted heteroarylalkyl, heteroarylalkyoxy, substituted heteroarylalkyloxy,
carboxyl, lower alkoxycarbonyl, substituted lower alkoxycarbonyl, aryloxycarbonyl,
substituted aryloxycarbonyl, arylalkyloxycarbonyl, substituted arylalkyloxycarbonyl,
carbamate, substituted carbamate, carbamoyl, substituted carbamoyl, sulfamoyl,
substituted sulfamoyl and a group of the fonnula -1-R14, where "L" is a linker and R14
is cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl,
provided that at least one of R2 or R6 is other than hydrogen;
Rn is hydrogen or lower alkyl; and
R12 is monohalomethyl or dihalomethyl.
2. The compound of Claim 1, wherein the compound is not compound 9 or
compound 159.
3. The compound of Claim 2 in which R11 is hydrogen and R12 is
dichloromethyl or dibromomethyl.
4. The compound of Claim 2 in which Z is CH.
5. The compound of Claim 3 in which X is O and Y is N.
6. The compound of Claim 3 in which X is N and Y is O.
7. The compound of Claim 3 in which X and Y are each N.
8. The compound of Claim 2 in which Z is N.
9. The compound of any one of Claims 2-8 in which R8,R9,R10 and R13 are
each hydrogen.
10. The compound of any one of Claims 2-8 in which R3 and Rs are each
hydrogen.
11. The compound of Claim 10 in which R4 is -1-R14.
12. The compound of Claim 11 in which L is -O-(CH2)1-3- and R14 is
N-morpholinyl.
13. The compound of any one of Claims 2-8 in which R3, R4 and R5 are each
hydrogen.
14. The compound of Claim 13 in which R2 and R6 are each, independently of
one another, selected from the group consisting of-OH, -NO2, halo, fluoro, chloro,
Bromo, iodo, lower alkyl, methyl, lower heteroalkyl, (C3-C6) cycloalkyl, 5- or 6-
membered cycloheteroalkyl, N-morpholinyl, N-methyl-N-piperazinyl, N-
piperadinyl, substituted N-piperadinyl, 4-(N-piperadinyl)-N-piperadinyl, 4-amino-
N piperadinyl, lower aikoxy, methoxy, ethoxy, lower alkylthio, methylthio, lower
haloalkyl, monohalomethyl, dihalomethyl, trihalomethyl, trifluoromethyl, lower
haloalkyloxy, monohalomethoxy, dihalomethoxy, trihalomethoxy,
trifluoromethoxy, aryl, phenyl, aryialky), benzyl, aryloxy, phenoxy, arylalkyloxy,
benzyloxy, 5- or 6-membered heteroaryl, lower alkyloxycarbonyl, sulfamoyl and -
L-R14 , where L is -(CH2)1-3-or -O-(CH2) 1-3- and R14 is a 5- or 6-membered
cycloheteroalkyl or N-morpholinyl.
15. The compound as claimed in Claim 2 wherein R2, R3, R4, R5, R6, R8, R9, R10,
and R13, are selected from the substituents delineated in TABLE 1.
16. The compound as claimed in Claim 2, which is selected from any compound
in TABLE 1, or a corresponding pyrazole, isoxazole or oxadiazole analog or
regioisomer thereof.
17. The compound as claimed in Claim 16 which inhibits HCV replication and/or
proliferation with an IC50 of 10 uM or less, as measured in an in vitro assay.
18. A composition comprising a pharmaceutically acceptable vehicle and a
compound according to Claim 1.
19. The composition as claimed in Claim 18, which is a liposome suspension.
20. The composition as claimed in Claim 19, which comprises from about 0.5-30
mg/ml of the compound and about 100-200 mg/ml of a phospholipid in water.
21.The composition as claimed in Claim 20, which further includes about 5
mg/ml of cholesterol.
22. An intermediate compound useful for synthesizing substituted diphenyl
heterocycle compounds, said intermediate compound having a structure
defined by structural formula (II)
Where R15 is NO2 or NHR, where R is hydrogen, lower alky I or a protecting
group and X, Y, Z, R2, R3, R4, R5, R6, R8, R9, R10, and R13, are as defined in
Claim 1, or a protected analog of the compound of structural formula (II)
23. A method of synthesizing a substituted diphenyl heterocycle compound
according to structural formula (I)
Wherein X, Y, Z, R2, R3, R4, R5, R6, R8, R9, R10, R11, R12 and R°, are as
defined in Claim 1, comprising the steps of (1) optionally alkylating a
compound as claimed in claim 22 in which R11 is NHR with R11 -halide, (2)
optionally deprotecting the product of step (1) and (3) acylating the product
of (1) or (2) with LG-C (O)-R12, where LG is a leaving group or an activating
group, thereby yielding a compound according to structural formula (I)
The present invention relates to substituted diphenyl heterocycle compounds and
pharmaceutical compositions thereof that inhibit replication of HCV virus. The
present invention also relates to the use of the compounds and/or compositions
to inhibit HCV replication and/or proliferation and to treat or prevent HCV
infections.

Documents:


Patent Number 224958
Indian Patent Application Number 00586/KOLNP/2004
PG Journal Number 44/2008
Publication Date 31-Oct-2008
Grant Date 29-Oct-2008
Date of Filing 05-May-2004
Name of Patentee RIGEL PHARMACEUTICALS, INC.
Applicant Address 1180 VETERANS BLVD., SOUTH SAN FRANCISCO, CA 94080
Inventors:
# Inventor's Name Inventor's Address
1 SINGH, RAJINDER 3180 OAK ROAD, NO. 318 WALNUT CREEK, CA 94596
2 LU, HENRY 1031 FLYING FISH STREET, FOSTER CITY, CA 94404
3 SUN, THOMAS 4378 OTHELLO DRIVE, FREMONT, CA 94555
4 GOFF, DANE 77 MARKHAM AVENUE, REDWOOD CITY, CA 94063
5 ISSANKANI, SARKIZ, D. 190 COLONADE SQUARE, SAN JOSE, CA 95127
PCT International Classification Number C07D 261/08
PCT International Application Number PCT/US02/35131
PCT International Filing date 2002-11-01
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/350,107 2001-11-02 U.S.A.
2 60/405,472 2002-08-23 U.S.A.