Indian Patents. 201834:PROCESS FOR PREPARATION OF LAMOTRIGINE CRYSTALLINE POLYMORPHS

Title of Invention	PROCESS FOR PREPARATION OF LAMOTRIGINE CRYSTALLINE POLYMORPHS
Abstract	The present invention relates to a process for preparation of lamotrigine crystalline polymorphs.

Full Text	The present invention relates to novel crystalline forms of lamotrigine, to processes for their preparation and pharmaceutical compositions containing them. BACKGROUND OF THE INVENTION Lamotrigine of formula (1): or 6-(2,3-Dichlorophenyl)-1,2,4-triazine-3,5-diamine is an anti-epileptic drug and its therapeutic uses are disclosed in U.S. Pat. No. 4,602,017. Different synthetic methods of lamotrigine are described in WO 01/049669, US 6,111,101, US 6,333,198, US 5,912,345, EP 800521, US 4,602,017. Various polymorphic forms are disclosed in WO 02/068398. We have discovered three novel crystalline forms of lamotrigine. The novel forms have been found to be stable over the time and does not automatically convert into other crystalline forms of lamotrigine. The novel forms of lamotrigine is, thus, suitable for pharmaceutical preparations. Thus the object of the present invention is to provide stable novel crystalline forms of lamotrigine, to provide a processes for preparation of the novel crystalline forms and to provide a pharmaceutical compositions comprising these novel crystalline forms. SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided a novel crystalline Form I of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 12.5. 13.9, 16.7, 18.0, 22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees. Figure 1 shows typical Form I x-ray powder diffraction pattern. According to another aspect of the present invention, there is provided a novel crystalline Form II of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0, 17.4, 18.0, 18.2, 18.7, 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1, 27.5, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4, 32.9, 35.3, 35.7, 36.5 degrees. Figure 2 shows typical Form II x-ray powder diffraction pattern. According to another aspect of the present invention, there is provided a novel crystalline Form III of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 9.9, 12.0, 13.3, 16.1, 17.0, 18.1, 18.7, 19.5, 24.4, 26.0, 26.3, 27.6, 28.1, 37.1 degrees. Figure 3 shows typical Form III x-ray powder diffraction pattern. According to another aspect of the present invention there is provided a process for preparation of Form I lamotrigine comprising the steps of: a) dissolving lamotrigine in an ester; b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours; c) filtering Form I lamotrigine. The ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate. According to another aspect of the present invention there is provided a process for preparation of Form II lamotrigine comprising the steps of: a) dissolving lamotrigine in dioxane; b) maintaining at about 15°C to about 30°C for about 1 hour to 3 hours; c) filtering Form II lamotrigine. According to another aspect of the present invention there is provided a process for preparation of Form III lamotrigine comprising the steps of: a) mixing lamotrigine, isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C; b) filtering the Form III lamotrigine at about 20°C to about 30°C. Lamotrigine prepared by any of the known methods can be used in the above processes. Lamotrigine solvate or hydrate may also be used in the above processes. According to another aspect of the present invention there is provided a pharmaceutical composition comprising Form I or Form 11 or Form III lamotrigine. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a x-ray powder diffraction pattern of Form I lamotrigine. Figure 2 is a x-ray powder diffraction pattern of Form II lamotrigine. Figure 3 is a x-ray powder diffraction pattern of Form III lamotrigine. x-Ray powder diffraction spectrum was measured on a Siemens diffractometer. DETAILED DESCRIPTION OF THE INVENTION According to one aspect of the present invention, there is provided a novel crystalline Form I of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 20 at about 12.5, 13.9, 16.7, 18.0, 22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees. Figure 1 shows typical Form I x-ray powder diffraction pattern. According to another aspect of the present invention, there is provided a process for preparation of Form I lamotrigine. Thus lamotrigine is dissolved in an ester. The ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate. The Form I lamotrigine is maintained at about 15°C to about 30°C, preferably at about 20°C to about 25°C, for about 30 minutes to about 2 hours and filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used. According to another aspect of the present invention, there is provided a novel crystalline Form II lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0, 17.4, 18.0, 18.2, 18.7, 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1, 27.4, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4. 32.9, 35.3, 35.7, 36.5 degrees. Figure 2 shows typical Form II x-ray powder diffraction pattern. According to another aspect of the present invention there is provided a process for preparation of Form II lamotrigine. Thus lamotrigine is dissolved in dioxane and maintained at about 15°C to about 30°C for about 1 hour to 3 hours. The separated Form II lamotrigine is filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used. According to another aspect of the present invention, there is provided a novel crystalline Form III of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 9.9, 12.0, 13.3, 16.1, 17.0, 18.1, 18.7, 19.5, 24.4, 26.0, 26.3. 27.6, 28.1, 37.1 degrees. Figure 3 shows typical Form III x-ray powder diffraction pattern. According to another aspect of the present invention there is provided a process for preparation of Form III lamotrigine. Thus lamotrigine isopropyl acetate, chloroform and dimethyl formamide are mixed and heated to about 60°C to about 70°C. The contents are maintained for about 30 minutes and cooled to about 20°C to about 30°C. The Form III lamotrigine is filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used. According to another aspect of the present invention there is provided a pharmaceutical composition comprising Forni I or Form II or Fomn III lamotrigine. The forms of lamotrigine may be formulated in a form suitable for oral administration or injection. The following examples are given for the purpose of illustrating the present invention and should not be considered as limitations on the scope or spirit of the invention. Example 1 Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is mixed with ethyl acetate (100 ml) and maintained at about 70°C for 30 minutes. Then the contents are cooled to about 20°C. The solid is separated by filtration to give 9.0 gm of Form I lamotrigine. Example 2 Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is added to dioxane (100 ml), maintained at 50°C to 55°C for 30 minutes, cooled to 25°C and maintained at this temperature for 2 hours. The solid is separated by filtration to give 8.5 gm of Form II lamotrigine. Example 3 Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is added to isopropyl acetate (150 ml) and the contents are heated to about 65°C. Chloroform (50 ml) and dimethyl formamide (48 ml) are added at this temperature and stirred for 30 minutes. The contents are cooled to 25°C and filtered to give 9.5 gm of Form III lamotrigine. Example 4 Example 1 is repeated using Form II lamotrigine instead of lamotrigine to give Form I lamotrigine. Example 5 Example 1 is repeated using Form III lamotrigine instead of lamotrigine to give Form I lamotrigine. Example 6 Example 2 is repeated using Form III lamotrigine instead of lamotrigine to give Form II lamotrigine. Example 7 Example 2 is repeated using Form I lamotrigine instead of lamotrigine to give Form II lamotrigine. Example 8 Example 3 is repeated using Form II lamotrigine instead of lamotrigine to give Form III lamotrigine. Example 9 Example 3 is repeated using Fomi I lamotrigine instead of lamotrigine to give Form III lamotrigine. We claim: 1. A process for the preparation of the lamotrigine crystalline polymorph, Form I, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 12.5, 13.9, 16.7, 18.0, 22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees as shown in figure 1; Form II, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0, 17.4, 18.0, 18.2, 18.7. 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1, 27.5, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4, 32.9, 35.3, 35.7, 36.5 degrees as shown in figure 2; or Form III, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 9.9. 12.0, 13.3, 16.1, 17.0, 18.1, 18,7, 19.5, 24.4, 26.0, 26.3, 27.6, 28.1, 37.1 degrees as shown in figure 3; as herein described comprising the steps of: a) dissolving lamotrigine in a solvent selected either from an ester solvent such as ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate or from dioxane or from a mixture of isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C; and b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours and filtering the lamotrigine crystalline Form I; or maintaining at about 15°C to about 30°C for about 1 hour to 3 hours and filtering the lamotrigine crystalline Form II; or filtering the lamotrigine crystalline Form III at about 20°C to 30°C. 2. The process as claimed in claim 1, wherein the process comprising the steps of: a) dissolving lamotrigine in an ester; b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours; c) filtering Form I lamotrigine; wherein ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate. 3. The process as claimed in claim 1, wherein the process comprising the steps of: a) dissolving lamotrigine in dioxane; b) maintaining at about 15°C to about 30°C for about 1 hour to 3 hours; c) filtering Form II lamotrigine. 4. The process as claimed in claim 1, wherein the process comprising the steps of: a) mixing lamotrigine, isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C; b) filtering the Form III lamotrigine at about 20°C to about 30°C.

Full Text

The present invention relates to novel crystalline forms of lamotrigine, to processes for their preparation and pharmaceutical compositions containing them.
BACKGROUND OF THE INVENTION Lamotrigine of formula (1):

or 6-(2,3-Dichlorophenyl)-1,2,4-triazine-3,5-diamine is an anti-epileptic drug and its therapeutic uses are disclosed in U.S. Pat. No. 4,602,017.
Different synthetic methods of lamotrigine are described in WO 01/049669, US 6,111,101, US 6,333,198, US 5,912,345, EP 800521, US 4,602,017.
Various polymorphic forms are disclosed in WO 02/068398.
We have discovered three novel crystalline forms of lamotrigine. The novel forms have been found to be stable over the time and does not automatically convert into other crystalline forms of lamotrigine.
The novel forms of lamotrigine is, thus, suitable for pharmaceutical preparations.
Thus the object of the present invention is to provide stable novel crystalline forms of lamotrigine, to provide a processes for preparation of the novel crystalline forms and to provide a pharmaceutical compositions comprising these novel crystalline forms.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a novel crystalline Form I of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 12.5. 13.9, 16.7, 18.0, 22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees. Figure 1 shows typical Form I x-ray powder diffraction pattern.

According to another aspect of the present invention, there is provided a novel crystalline Form II of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0, 17.4, 18.0, 18.2, 18.7, 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1, 27.5, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4, 32.9, 35.3, 35.7, 36.5 degrees. Figure 2 shows typical Form II x-ray powder diffraction pattern.
According to another aspect of the present invention, there is provided a novel crystalline Form III of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 9.9, 12.0, 13.3, 16.1, 17.0, 18.1, 18.7, 19.5, 24.4, 26.0, 26.3, 27.6, 28.1, 37.1 degrees. Figure 3 shows typical Form III x-ray powder diffraction pattern.
According to another aspect of the present invention there is provided a process for preparation of Form I lamotrigine comprising the steps of:
a) dissolving lamotrigine in an ester;
b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours;
c) filtering Form I lamotrigine.
The ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate.
According to another aspect of the present invention there is provided a process for preparation of Form II lamotrigine comprising the steps of:
a) dissolving lamotrigine in dioxane;
b) maintaining at about 15°C to about 30°C for about 1 hour to 3 hours;
c) filtering Form II lamotrigine.
According to another aspect of the present invention there is provided a process for preparation of Form III lamotrigine comprising the steps of:
a) mixing lamotrigine, isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C;
b) filtering the Form III lamotrigine at about 20°C to about 30°C.
Lamotrigine prepared by any of the known methods can be used in the above processes. Lamotrigine solvate or hydrate may also be used in the above processes.
According to another aspect of the present invention there is provided a pharmaceutical composition comprising Form I or Form 11 or Form III lamotrigine.

BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a x-ray powder diffraction pattern of Form I lamotrigine.
Figure 2 is a x-ray powder diffraction pattern of Form II lamotrigine.
Figure 3 is a x-ray powder diffraction pattern of Form III lamotrigine.
x-Ray powder diffraction spectrum was measured on a Siemens
diffractometer.
DETAILED DESCRIPTION OF THE INVENTION
According to one aspect of the present invention, there is provided a novel crystalline Form I of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 20 at about 12.5, 13.9, 16.7, 18.0,
22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees. Figure 1
shows typical Form I x-ray powder diffraction pattern.
According to another aspect of the present invention, there is provided a process for preparation of Form I lamotrigine. Thus lamotrigine is dissolved in an ester. The ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate. The Form I lamotrigine is maintained at about 15°C to about 30°C, preferably at about 20°C to about 25°C, for about 30 minutes to about 2 hours and filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used.
According to another aspect of the present invention, there is provided a novel crystalline Form II lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0,
17.4, 18.0, 18.2, 18.7, 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1,
27.4, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4. 32.9, 35.3, 35.7, 36.5 degrees. Figure 2 shows typical Form II x-ray powder diffraction pattern.
According to another aspect of the present invention there is provided a process for preparation of Form II lamotrigine. Thus lamotrigine is dissolved in dioxane and maintained at about 15°C to about 30°C for about 1 hour to 3 hours. The separated Form II lamotrigine is filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used.

According to another aspect of the present invention, there is provided a novel crystalline Form III of lamotrigine characterized by an x-ray powder diffraction pattern having peaks expressed as 29 at about 9.9, 12.0, 13.3, 16.1, 17.0, 18.1, 18.7, 19.5, 24.4, 26.0, 26.3. 27.6, 28.1, 37.1 degrees. Figure 3 shows typical Form III x-ray powder diffraction pattern.
According to another aspect of the present invention there is provided a process for preparation of Form III lamotrigine. Thus lamotrigine isopropyl acetate, chloroform and dimethyl formamide are mixed and heated to about 60°C to about 70°C. The contents are maintained for about 30 minutes and cooled to about 20°C to about 30°C. The Form III lamotrigine is filtered. Lamotrigine prepared by any of the known methods can be used in the process. Lamotrigine solvate or hydrate may also be used.
According to another aspect of the present invention there is provided a pharmaceutical composition comprising Forni I or Form II or Fomn III lamotrigine. The forms of lamotrigine may be formulated in a form suitable for oral administration or injection.
The following examples are given for the purpose of illustrating the present invention and should not be considered as limitations on the scope or spirit of the invention.
Example 1
Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is mixed with ethyl acetate (100 ml) and maintained at about 70°C for 30 minutes. Then the contents are cooled to about 20°C. The solid is separated by filtration to give 9.0 gm of Form I lamotrigine.
Example 2
Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is added to dioxane (100 ml), maintained at 50°C to 55°C for 30 minutes, cooled to 25°C and maintained at this temperature for 2 hours. The solid is separated by filtration to give 8.5 gm of Form II lamotrigine.
Example 3
Lamotrigine (10 gm) (obtained by the process described in example 1 of US 4,602,017) is added to isopropyl acetate (150 ml) and the contents are heated to about 65°C. Chloroform (50 ml) and dimethyl formamide (48 ml) are

added at this temperature and stirred for 30 minutes. The contents are cooled to 25°C and filtered to give 9.5 gm of Form III lamotrigine.
Example 4 Example 1 is repeated using Form II lamotrigine instead of lamotrigine to give Form I lamotrigine.
Example 5 Example 1 is repeated using Form III lamotrigine instead of lamotrigine to give Form I lamotrigine.
Example 6 Example 2 is repeated using Form III lamotrigine instead of lamotrigine to give Form II lamotrigine.
Example 7 Example 2 is repeated using Form I lamotrigine instead of lamotrigine to give Form II lamotrigine.
Example 8 Example 3 is repeated using Form II lamotrigine instead of lamotrigine to give Form III lamotrigine.
Example 9 Example 3 is repeated using Fomi I lamotrigine instead of lamotrigine to give Form III lamotrigine.

We claim:
1. A process for the preparation of the lamotrigine crystalline polymorph, Form I, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 12.5, 13.9, 16.7, 18.0, 22.3, 23.6, 26.8, 27.9, 28.5, 28.9, 29.4, 31.7, 40.2, 42.3 degrees as shown in figure 1; Form II, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 8.9, 11.2, 12.3, 13.2, 13.9, 17.0, 17.4, 18.0, 18.2, 18.7. 19.8, 21.4, 22.1, 22.7, 25.1, 25.4, 25.7, 26.4, 26.8, 27.1, 27.5, 28.3, 28.8, 29.2, 30.1, 30.9, 31.4, 32.9, 35.3, 35.7, 36.5 degrees as shown in figure 2; or Form III, characterized by an x-ray powder diffraction pattern having peaks expressed as 26 at about 9.9. 12.0, 13.3, 16.1, 17.0, 18.1, 18,7, 19.5, 24.4, 26.0, 26.3, 27.6, 28.1, 37.1 degrees as shown in figure 3; as herein described comprising the steps of:
a) dissolving lamotrigine in a solvent selected either from an ester solvent such as ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate or from dioxane or from a mixture of isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C; and
b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours and filtering the lamotrigine crystalline Form I; or maintaining at about 15°C to about 30°C for about 1 hour to 3 hours and filtering the lamotrigine crystalline Form II; or filtering the lamotrigine crystalline Form III at about 20°C to 30°C.
2. The process as claimed in claim 1, wherein the process comprising the steps
of:
a) dissolving lamotrigine in an ester;
b) maintaining at 15°C to 30°C for about 30 minutes to 2 hours;
c) filtering Form I lamotrigine;
wherein ester is selected from the group consisting of ethyl acetate, methyl acetate, ethyl formate, isopropyl acetate.
3. The process as claimed in claim 1, wherein the process comprising the steps
of:
a) dissolving lamotrigine in dioxane;
b) maintaining at about 15°C to about 30°C for about 1 hour to 3 hours;
c) filtering Form II lamotrigine.

4. The process as claimed in claim 1, wherein the process comprising the steps of:
a) mixing lamotrigine, isopropyl acetate, chloroform and dimethyl formamide at about 60°C to about 70°C;
b) filtering the Form III lamotrigine at about 20°C to about 30°C.

Documents:

710-chenp-2003-abstract.pdf

710-chenp-2003-claims duplicate.pdf

710-chenp-2003-claims original.pdf

710-chenp-2003-correspondnece-others.pdf

710-chenp-2003-correspondnece-po.pdf

710-chenp-2003-description(complete) duplicate.pdf

710-chenp-2003-description(complete) original.pdf

710-chenp-2003-drawings.pdf

710-chenp-2003-form 1.pdf

710-chenp-2003-form 3.pdf

710-chenp-2003-form 5.pdf

710-chenp-2003-others.pdf

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Patent Number

201834

Indian Patent Application Number

710/CHENP/2003

PG Journal Number

08/2007

Publication Date

23-Feb-2007

Grant Date

07-Aug-2006

Date of Filing

12-May-2003

Name of Patentee

M/S. HETERO DRUGS LIMITED

Applicant Address

HETERO HOUSE, 83-3-166/7/1, ERRAGADDA, HYDERABAD-500 018, ANDHRA PRADESH, INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	PARTHASARADHI REDDY, BANDI	HETERO HOUSE, 83-3-166/7/1, ERRAGADDA, HYDERABAD-500 018, ANDHRA PRADESH, INDIA
2	RAJI REDDY, RAPOLU	HETERO DRUGS LIMITED (R & D) PLOT NO.B-80 & 81, A.P.I.E., BALANAGAR, HYDERABAD-500 018 ANDHRA PRADESH, INDIA
3	MURALIDHARA REDDY, DASARI	HETERO DRUGS LIMITED (R & D) PLOT NO.B-80 & 81, A.P.I.E., BALANAGAR, HYDERABAD-500 018 ANDHRA PRADESH, INDIA
4	RATHNAKAR REDDY, KURA	HETERO DRUGS LIMITED (R & D) PLOT NO.B-80 & 81, A.P.I.E., BALANAGAR, HYDERABAD-500 018 ANDHRA PRADESH, INDIA
5	SUBASH CHANDER REDDY, KESIREDDY	HETERO DRUGS LIMITED (R & D) PLOT NO.B-80 & 81, A.P.I.E., BALANAGAR, HYDERABAD-500 018 ANDHRA PRADESH, INDIA

PCT International Classification Number

C07D 253/75

PCT International Application Number

PCT/IN03/00057

PCT International Filing date

2003-03-17

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA