Title of Invention

"PYRROLO [2,1-C][1,4] BENZODIAZEPINE-ANTHRAQUINONE CONJUGATES USEFUL AS ANTTUMOUR AGENTS"

Abstract

The present invention relates to novel pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids useful as potential antitumour agents. The present invention also relates to the synthesis of pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids as usefiil anticancer agents. The structural frrmula of novel pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids (V) is as follows, wherein n = 3,4; R = H, OH.

Full Text

PYRR0L0[2,1-C1 [l,4]BENZODIAZEPmE-ANTHRAQUINONE CONJUGATES USEFUL AS ANTITUMOUR AGENTS Field of the invention The present invention relates to novel pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids useful as potential antitumour agents. The present invention also relates to the synthesis of pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids as useful anticancer agents. The structural formula of novel pyrrolo[2,l-c][l,4]benzodiazepine-anthraquinone hybrids (V) is as follows, wherein n = 3,4; R = H, OH. (FORMULA REMOVED) Background of the invention Pyrrolo[2,l-c][l,4]benzodiazepines are a family of DNA interactive antitumour antibiotics derived from streptomyces species. Examples of naturally occurring pyrrolo[2,l-c][l,4] benzodiazepines include anthramycin, tomaymycin, sibiromycin and DC-81. These compounds show their biological activity through covalent binding via their NlO-Cll imine/carbinol amine moiety to the C2-amine position of a guanine residue within the minor groove of DNA giving rise to the preference for pu-G-pu sequences. (Kunimoto, S.; Masuda, T.; Kanbayashi, N.; Hamada, M.; Naganawa, H.; Miyamoto, M.; Takeuchi, T and Unezawa, H. J. Antibiot., 1980, 33, 665.; Kohn, K. W. and Speous, C. L. J. Mol. Biol., 1970, 91, 551.; Hurley, L. H.; Gairpla, C. and Zmijewski, M. Biochem. Biophy. Acta., 1977, 475, 521.; Kaplan, D. J. and Hurley, L. H. Biochemistry, 1981, 20, 7572.) The molecules have a right-handed twist, when viewed from the C-ring towards the A-ring. This enables the PBD to mirror the curvature of B-form DNA and maintain isohelical contact with the walls and floor of the minor groove. In the last few years a growing interest has been shown in the development of new pyrrolo[2,l-c][l,4]benzodiazepine.hybrids. Many PBD conjugates have been synthesized and investigated for their anticancer activity. (Thurston, D. E.; Morris, S. J.; Hartley, J. A. Chem. Commun. 1996, 563.; Damayanthi, Y.; Reddy, B. S. P.; Lown, J. W. J. Org. Chem. 1999, 64, 290.; Kamal, A.; Reddy, B. S. N.; Reddy, G. S. K.; Ramesh, G Bioorg. Med. Chem. Lett. 2002, 12, 1933). Recently C-8 linked PBD dimers with C2/C2 exounsaturation have been designed and synthesized (Gregson, S. J.; Howard, P. W.; Hartley, J. A.; Brooks, N. A.; Adam, L. J.; Jenkins, T. C; Kelland, L. R. and Thurston, D. E., J. Med. Chem. 2001, 44, 737). Recently, a non cross-linking mixed imine-amide PBD dimers have been synthesized that have significant DNA binding ability and potent antitumor activity (Kamal, A.; Ramesh, G.; Laxman, N.; Ramulu, P.; Srinivas, O.; NeeHma, K.; Kondapi, A. K.; Srinu, V. B.; Nagarajaram, H. M. J. Med. Chem. 2002, 45, 4679). (FORMULA REMOVED) imine-amide PBD dimers Objects of the invention The main object of the invention is to provide new pyrrolo[2,l-c][l,4]benzodiazepines useful as anticancer agents. Another object of the invention is to provide a process for the preparation of novel pyrrolo[2,l-c][l,4]benzodiazepines useful as antitumor agents. Summary of the invention Accordingly, the present invention provides a novel pyrrolo[2,l-c][l,4]benzodiazepine of formula V where n = 3, 4; R = H, OH. (FORMULA REMOVED) In one embodiment of the invention, the compound is 7-Methoxy-8-[N-(9,10-dihydro- 9,10-dioxo-l-anthracenyl)-alkane-n-carboxamide]-oxy-(l laS)-l,2,3,l la tetrahydro-5H- pyrrolo [2,l-c][l,4]benzodiazepin-5-one of formula V given below where the alkane is selected from propane and butane (FORMULA REMOVED) In a further embodiment of the invention, the compound is 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3 -carboxamide]-oxy-( 11 aS)- 1,2,3,11a tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one of structural formula shown below: In a further embodiment of the invention, the compound is 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3 -carboxamide]-oxy-(4R)-hydroxy-( 11 aS)-1,2,3,11a tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. In a further embodiment of the invention, the compound is 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-butane-4-carboxamide]-oxy-(l laS)-l,2,3,l la tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one and of structural formula shown below. (FORMULA REMOVED) In a further embodiment of the invention, the compound is 7-Methoxy-8-ps[-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy-(4R)-hydroxy-(l 1 aS)-1,2,3,11 a tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. (FORMULA REMOVED) The present invention also provides a process for the preparation of a novel pyrrolo[2, l-c][l,4]ben2;odiazepine of formula V where n = 3, 4; R = H, OH (FORMULA REMOVED) which comprises reacting N-(9,10-dihydro-9,l 0-dioxo-l-anthracenyl)-l-bromo-alkanamide of formula I (FORMULA REMOVED) with (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrroUdine-2-carboxaldehyde diethyl thioacetal of formula II (FORMULA REMOVED) in an aprotic water miscible organic solvent in the presence of a mild inorganic base at refluxing temperature for a period of 48h, isolating 2S-N-{4-[N-(9,10-dihydro-9,l 0-dioxo-1-antliracenyl)-alkane-3-carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula III (FORMULA REMOVED) reducing it with SnCl2.2H20 in presence of organic solvent at reflux temperature, isolating the 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-alkane-3-carboxamide]-oxy-5-methoxy-2-aminobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula IV, (FORMULA REMOVED) reacting the amino compound of formula IV with known deprotecting agents in a conventional manner to give novel pyrrol[2,l-c][l,4]benzodiazepine of formula V wherein n and R are as stated above. The present invention also relates to a pharmaceutical composition for use as an anticancer agent comprising a pharmaceutically acceptable amount of a pyrrolo[2,l-c][l,4]benzodiazepine of formula V where n = 3, 4; R = H, OH and one or more pharmaceutically acceptable excipients. (FORMULA REMOVED) The present invention also relates to a method for the treatment of cancer in a subject comprising administering to the subject a pharmaceutically effective amount of a pyrrolo[2,l-c][l,4]benzodiazepine of formula V where n = 3, 4; R = H, OH (FORMULA REMOVED) In one embodiment of the invention, the cancer comprises a human cancer cell line selected from the group consisting of HT-29, HCT-15, A-549, HOP-62 and SiHa. In another embodiment of the invention, the subject is a mammal. In a further embodiment of the invention, the subject is a human. The present invention also relates to the use of a pyrrolo[2,l-c][l,4]benzodiazepine of formula V where n = 3, 4; R = H, OH for the treatment of cancer in a subject (FORMULA REMOVED) In one embodiment of the invention, the cancer comprises a human cancer cell line selected from the group consisting of HT-29, HCT-15, A-549, HOP-62 and SiHa. In another embodiment of the invention, the subject is a mammal. In a further embodiment of the invention, the subject is a human. Detailed description of the invention The invention provides a novel pyrrolo[2,l-c][l,4]benzodiazepine of formula V wheren = 3, 4;R = H, OH. (FORMULA REMOVED) The compound of formula V obtained in the invention is preferably 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-alkane-n-carboxamide]-oxy-( 11 aS)-1,2,3,11 a tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one of formula V given below where the alkane is selected from propane and butane (FORMULA REMOVED) The compounds of formula V may be any one of the following: (a) 7-Methoxy-8-[lSf-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3-carboxamide]-oxy- (llaS)-l,2,3,lla tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one of structural formula shown below: (FORMULA REMOVED) (b) 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3-carboxamide]-oxy- (4R)-hydroxy-(llaS)-l,2,3,lla tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. (FORMULA REMOVED) (c) 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy- (llaS)-l,2,3,lla tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one and of structural formula shown below. (FORMULA REMOVED) (d) 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy- (4R)-hydroxy-(llaS)-l,2,3,lla tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. (FORMULA REMOVED) The compounds of the invention are prepared by a process comprising reacting N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-1 -bromo-alkanamide of formula I (FORMULA REMOVED) with (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrrolidine-2-carboxaldehyde diethyl thioacetal of formula II (FORMULA REMOVED) in an aprotic water miscible organic solvent in the presence of a mild inorganic base at refluxing temperature for a period of 48h. The 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-alkane-3-carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula III (FORMULA REMOVED) obtained is isolated and reduced with SnCl2.2H20 in presence of organic solvent at reflux temperature. The 2S-N-{4-[N-(9, lO-dihydro-9,10-dioxo-l-anthracenyl)-alkane-3- carboxamide]-oxy-5-methoxy-2-aminobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula IV, (FORMULA REMOVED) obtained thereby is isolated and reacted with a known deprotecting agent in a conventional manner to give novel pyrrol[2,l-c][l,4]benzodiazepine of formula V wherein n and R are as stated above. The compound of the invention (formula V) may be administered in the form of a pharmaceutical composition comprising a pharmaceutically acceptable amount thereof and one or more pharmaceutically acceptable excipients. The present invention also relates to a method for the treatment of cancer in a subject comprising administering to the subject a pharmaceutically effective amount of a pyrrolo[2,l-c][l,4]benzodiazepine of formula V where n = 3, 4; R = H, OH (FORMULA REMOVED) The compound has been found effective against human cancer cell line selected from the group consisting of HT-29, HCT-15, A-549, HOP-62 and SiHa as can be seen from the cytotoxicity data given below. The precursors, N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-l-bromo-alkanamide of formula I (Collier, D. A.; Neidle, S.; J. Med. Chem., 1988, 847) and (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrrolidine-2-carboxaldehyde diethyl thio-acetal of formula 11 (Thurston, D. E.; Murthy, V. S.; Langley, D. R.; Jones, G.; B. Synthesis, 1990, 81) have been prepared by literature methods. Some representative compounds of formula V of present invention are given below: 1. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3 -carboxamide]-oxy-(llaS)-l,2,3,llatetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one 2. 7-Methoxy-8-[N-(9,10-dihydro-9,l 0-dioxo-l-anthracenyl)-propane-3-carboxamide]-oxy-(4R)-hydroxy-(l laS)-l,2,3,l la tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one 3. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy-(1 laS)-l,2,3,l latetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one 4. 7-Methoxy-8-pSf-(9,10-dihydro-9,10-dioxo-1 -antliracenyl)-butane-4-carboxamide]-oxy-(4R)-hydroxy-(llaS)-l,2,3,l latetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one These new analogues of pyrrlo [2,l-c][l,4]benzodiazepine hybrids have shown promising anticancer activity in various cell lines. The molecules synthesized are of immense biological significance with potential sequence selective DNA-binding property. This resulted in design and synthesis of new congeners as illustrated in scheme-I which comprises The ether linkage at C-8 position of DC-81 intermediates with Anthraquinone moiety. Refluxing the reaction mixture for 24-48h. Synthesis of C-8 hnked PBD hybrids. Purification by column chromatography using different solvents like ethyl acetate, hexane, dichloromethane and methanol. (FORMULA REMOVED) The following examples are given by way of illustration and therefore should not be construed to as limiting the scope of the present invention. Example 1 To a solution of (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrrolidine-2-carboxaldehyde diethyl thioacetal (400 mg, 1 m.mol) of formula II in acetone were added anhydrous K2CO3 (553 mg, 4 m.mol) and N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-l-bromo-propanamide (372 mg, 1 m.mg) of formula I and the mixture was refluxed for 48h.After completion of reaction K2CO3 was removed by filtration and the solvent was evaporated under redused pressure, purification by column chromatography afforded compound III 1HNMR (CDC13) 1.21-1.38 (m, 6H), 1.53-2.42 (m, 6H), 2.62-2.81 (m, 6H), 3.10-3.28 (m, 2H), 3.91 (s, 3H), 4.25 (m, 2H), 4.65 (m, 1H), 4.80 (d, 1H), 6.74 (s, 1H), 7.68 (s, 1H), 7.71-7.85 (m, 3H), 8.0 (d, 1H), 8.20-8.30 (m, 2H), 9.15 (d, 1H), 12.38 (bs, 1H). To a solution of 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-propane-3- carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrroUdine-2-carbaxaldehyde diethyl thioacetal (692 mg, 1 m.mol) of formula III .in methanol was added SnCl2.2H20 (1128 mg, 5 m.mol) and the mixture was refluxed until the TLC indicated the completion of reaction. The methanol was evaporated and 10% NaHCOa solution was added. The aqueous layer was extracted with ethyl acetate. The combined organic phases dried over Na2S04 and evaporated under vacuum to afford the amino thioacetal (IV) and directly used in the next step. A solution of IV (662 mg, 1 m.mol) HgCl2 (624 mg, 2.3 m.mol) and CaCOs (250 mg, 2.5 mg) in CH3CN-H2O (4:1) was stirred at room temperature until the TLC indicated complete consumption of the starting material. The reaction mixture was diluted with ethyl acetate and filtered through a celite bed. The organic layer was concentrated, dried and purified by column chromatography to give the compound V. 1HNMR (CDC13) 2.05 (m, 2H), 2.20-2.40 (m, 4H), 2.81 (m, 2H), 3.50-3.81 (m, 3H), 3.91 (s, 3H), 4.15-4.26 (m, 2H), 6.76 (s, 1H), 7.42 (s, 1H), 7.55 (d, 1H), 7.80 (m, 3H), 8.0 (d, 1H), 8.2-8.3 (m, 2H), 9.15 (d, 1H), 12.38 (bs, 1H). Example 2 To a solution of (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrrolidine-2-carboxaldehyde diethyl thioacetal (400 mg, 1 m.mol) of formula II in acetone were added anhydrous K2CO3 (553 mg, 4 m.mol) and N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-l-bromo-butanamide (386 mg, 1 m.mg) of formula I and the mixture was refluxed for 48h. K2CO3 was removed by filtration and then the solvent was evaporated under redused pressure, purification by column chromatography afforded compound III 1HNMR (CDC13) 1.21-1.42 (m, 6H), 1.60-2.40 (m, 8H), 2.62-2.85 (m, 6H), 3.15-3.30 (m, 2H), 3.95 (s, 3H), 4.10-4.25 (m, 2H), 4.65 (m, 1H), 4.84 (d, 1H), 6.78 (s, 1H), 7.68 (s, 1H), 7.75-7.90 (m, 3H), 8.05 (d, 1H), 8.20-8.35 (m, 2H), 9.15 (d, 1H), 12.38 (bs, 1H). To a solution of 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-butane-3- carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrroUdine-2-carbaxaldehyde diethyl thioacetal (706 mg, 1 m.mol) of formula III .in methanol was added SnCl2.2H20 (1128 mg, 5 m.mol) and the mixture was refluxed until the TLC indicated completion of reaction. The methanol was evaporated and 10% NaHCOa solution was added. The aqueous layer was extracted with ethyl acetate. The combined organic phases dried over Na2S04 and evaporated under vacuum to afford the amino thioacetal (IV) and directly used in the next step. A solution of IV (676 mg, 1 m.mol) HgCl2 (624 mg, 2.3 m.mol) and CaCOs (250 mg, 2.5 mg) in CH3CN-H2O (4:1) was stirred at room temperature until the TLC indicated complete loss of the starting material. The reaction mixture was diluted with ethyl acetate and filtered through a celite bed. The organic layer was concentrated, dried and purified by column chromatography to give the compound V. ^HNMR (CDC13) 1.85-2.40 (m, 8H), 2.60-2.78 (m, 2H), 3.51-3.80 (m, 3H), 3.93 (s, 3H), 4.15-4.20 (m, 2H), 6.78 (s, 1H), 7.42 (s, 1H), 7.60 (d, 1H), 7.65-7.83 (m, 3H), 8.0 (d, 1H), 8.2-8.25 (m, 2H), 9.15 (d, 1H), 12.38 (bs, 1H). Biological activity: In vitro cytotoxicity against human cancer cell lines: Human cancer cell lines procured fi^om National Cancer Institute, Frederick, U.S.A or National Center for Cell Science; Pune, India, were used in present study. Cells were grown in tissue culture flasks in complete growth medium (RPMI-1640 medium with 2 mM glutamine, 100 ng/ml streptomycin, pH 7.4, sterilized by filtration and supplemented with 10% fetal calf serum and 100 units/ml penicillin before use) at 37°C in an atmosphere of 5% CO2 and 90% relative humidity in a carbon dioxide incubator. Cells at subconfluent stage were harvested from the flask by treatment with trypsin (0.5%) in PBS containing 0.02% EDTA) for determination of cytotoxicity. Cells with viability of more than 98% as determined by trypan blue exclusion were used for assay. Cell suspensions of required cell density were prepared in complete growth medium with gentamycin (50|ag/ml) for determination of cytotoxicity. Stock solutions of (2 X 10"^ M) of test material were prepared in DMSO (Dimethyl sulphoxide). The stock solutions were serially diluted with complete growth medium containing 50ng/ml of gentamycin to obtain working test solutions of required concentrations. In vitro cytotoxicity against human cancer cell lines was determined (Monks,A., Scudiero,D., Skehan,P., Shoemaker R., Paull, K., Vistica,D., Hose, C.,Langley, j., Cronise, P., Vaigro-WolfF, A., Gray-Goodrich, M., Campbell,H., Mayo, J and Boyd mJ. Natl. Cancer /m/., 1991,83, 757-766) using 96-well tissue culture plates. The 100 µl of cell suspension was added to each well of the 96-well tissue culture plate. The cells were incubated for 24 hours. Test materials in complete growth medium (100|al) were added after 24 hours incubation to the wells containing cell suspension. The plates were further incubated for 48 hours (at 37°C in an atmosphere of 5% and 90% relative humidity in a carbon dioxide incubator) after addition of test material and then the cell growth was stopped by gently layering trichloroacetic acid (TCA, 50µ1, 50%) on top of the medium in all the wells. The plates were incubated at 4°C for one hour to fix the cells attached to the bottom of the wells. The Uquid of all the wells was gently pipetted out and discarded. The plates were washed five times with distilled water to remove TCA, growth medium low molecular weight metabolites, serum proteins etc and air-dried. Cell growth was measured by staining with sulforhodamine B dye (Skehan et al, 1990). The adsorbed dye was dissolved in Tris-Buffer (100 m 1, O.OIM, pH 10.4) and plates were gently stirred for 5 minutes on a mechanical stirrer. The optical density was recorded on ELISA reader at 540 nm. The cell growth was calculated by subtracting mean OD value of respective blank from the mean OD value of experimental set. Percent growth in presence of test material was calculated considering the growth in absence of any test material as 100%and in turn percent growth inhibition in presence of test material will be calculated. Cytotoxicity: Compounds Va and Vc were evaluated for the primary anticancer activity Table 1. The percentage growth inhibition data for compound Va Table 2. The percentage growth inhibition data for compound Vc (TABLE REMOVED) We claim: 1. Pyrrolo[2,l -c][1, 4]benzodiazepine of formula V where n = 3, 4; R = H, OH. (Formula Removed) 2. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-alkane-n-carboxainide]-oxy- (llaS)-l,2,3,lla tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one of formula V given below where the alkane is selected from propane and butane (Formula Removed) 3. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-l -anthracenyl)-propane-3-carboxamide]- oxy-(11aS)-l,2,3,11a tetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one of structural formula shown below: (Structure Removed) 4. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-propane-3-carboxamide]- oxy-(4R)-hydroxy-(11aS)-l,2,3,11a tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. (Structure Removed) 5. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy- (llaS)-l,2,3,llatetrahydro-5H-pyrrolo [2,l-c][l,4]benzodiazepin-5-one and of structural formula shown below. (Structure Removed) 6. 7-Methoxy-8-[N-(9,10-dihydro-9,10-dioxo-1 -anthracenyl)-butane-4-carboxamide]-oxy- (4R)-hydroxy-(llaS)-l,2,3,lla tetrahydro-5H-pyrrolo[2,l-C][l,4] benzodiazepine-5-one and of structural formula shown below. (Structure Removed) 7. A process for the preparation of a novel pyrrolo[2,l-c][l,4]benzodiazepine of formula V wheren = 3, 4;R = H,0H which comprises (a) reacting N-(9,10-dihydro-9,l 0-dioxo-l-anthracenyl)-l-bromo-alkanamide of formula I I (Structure Removed) with (2S)-N-[4-hydroxy-5-methoxy-2-nitrobenzoyl]pyrroUdine-2-carboxaldehyde diethyl thioacetal of formula II (Structure Removed) in an aprotic water miscible organic solvent in the presence of a mild inorganic base at refluxing temperature to obtain 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-antliracenyl)-alk;ane- 3-carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula III (Structure Removed) (b) isolating the 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-alkane-3- carboxamide]-oxy-5-methoxy-2-nitrobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula III and reducing with SnC12.2H20 in presence of organic solvent at reflux temperature to obtain 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l-anthracenyl)-alkane- 3- carboxamide]-oxy-5-methoxy-2-aminobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula IV, (Structure Removed) (c) isolating 2S-N-{4-[N-(9,10-dihydro-9,10-dioxo-l -antliracenyl)-alkane-3- carboxamide]- oxy-5-methoxy-2-aminobenzoyl}pyrrolidine-2-carbaxaldehyde diethyl thioacetal of formula IV, and reacting the compound of formula IV with a deprotecting agent to obtain the pyrrol[2,l-c][l,4]benzodiazepine of formula V wherein n and R are as stated above. (Formula Removed) 8. A process as claimed in claim 7 wherein the inorganic base used in step (a) is selected from the group consisting of K2CO3. 9. A process as claimed in claim 7 wherein the aprotic water miscible solvent used in step (a) is acetone. 10. A process as claimed in claim 7 wherein step (a) is carried out for up to 48 hrs. 11. A process as claimed in claim 7 wherein the isolation of compound of formula III is carried out using column chromatography with removal of solvent being effected under reduced pressure and removal of K2CO3 being carried out by filtration. 12. A process as claimed in claim 7 wherein the organic solvent used in step (b) is methanol. 13. A process as claimed in claim 7 wherein the isolation of compound of formula IV in step (c) is effected by: (a) evaporating methanol followed by addition of NaHCOato obtain an aqueous layer; (b) extraction of the aqueous layer so obtained using ethyl acetate to obtain combined organic phases; (c) drying of the combined organic phases so obtained over Na2S04 and evaporating over vacuum. 14. A process as claimed in claim 7 wherein the deprotecting agent used in step (c) is HgC12.

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1423-del-2004-form-2.pdf

1423-DEL-2004-Form-3-(28-05-2012).pdf

1423-del-2004-form-3.pdf

1423-del-2004-form-5.pdf

1423-DEL-2004-Petition-137-(28-05-2012).pdf

abstract.jpg