Method for synthesizing leflunomide
US6723855B2 · kind B2 · utility
1Cited by
6References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 8, 2001 |
| Grant date | Apr 20, 2004 |
| Priority date | — |
| Expiry date | Mar 20, 2021 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61P37/06
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A process for synthesizing leflunomide from 5-methylisoxazole-4-carboxylic acid and 4-trifluoromethylaniline is provided in which the carboxylic acid group of 5-methylisoxazole-4-carboxylic acid is chlorinated, forming 5-methylisoxazole-4-carboxylic acid chloride. The acid chloride is then reacted without intermediate distillation with 4-trifluoromethylaniline in the presence of an alkali metal or alkaline-earth metal bicarbonate acid scavenger.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.