| Title of Invention | IMPROVED PROCESS FOR THE PREPARATION OF HIGHLY PURE 5-AMINO SALICYLIC ACID |
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| Abstract | The invention disclosed in this application relates to an improved process for the preparation of highly pure (>99.9%) 5-arnino salicylic acid which comprises dissolving 5-Nitro salicylic acid of formula (III) in aqueous alkaline solution, hydrogenating the alkaline solution with hydrogen gas in the presence of a metal catalyst at a pressure of 20-40 psi at room temperature for a period of 1-2 hours. filtering and adjusting the pH to 4.2-4.4 using a mineral acid, filtering washing with polar solvents, dissolving the crude product in 10% hydrochloric acid and treating with carbon precipitating the pure 5 amino salicylic acid by adjusting the pH using as base to 5.0 and maintaining it at room temperature for a period of 1-2 hours. Filtering & washing with methanol or acetone, preferably methanol. 5-amino salicylic acid prepared by the process is useful in the treatment of Chron's disease and ulcerative colitis. |
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1431-che-2004 amended claims 21-07-2011.pdf
1431-CHE-2004 CORRESPONDENCE OTHERS 21-07-2011.pdf
1431-che-2004 form-5 21-07-2011.pdf
1431-che-2004 correspondence others.pdf
| Patent Number | 248537 | |||||||||||||||
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| Indian Patent Application Number | 1431/CHE/2004 | |||||||||||||||
| PG Journal Number | 30/2011 | |||||||||||||||
| Publication Date | 29-Jul-2011 | |||||||||||||||
| Grant Date | 22-Jul-2011 | |||||||||||||||
| Date of Filing | 24-Dec-2004 | |||||||||||||||
| Name of Patentee | NATCO PHARMA LTD | |||||||||||||||
| Applicant Address | NATCO HOUSE,ROAD NO 2, BANJARA HILLS, HYDERABAD 500033, | |||||||||||||||
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| PCT International Classification Number | A61K 31/60 | |||||||||||||||
| PCT International Application Number | N/A | |||||||||||||||
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