Dihydropyridine-3, 5-dicarboxylic acid ester derivatives
US5616715A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 1995 |
| Grant date | Apr 1, 1997 |
| Priority date | — |
| Expiry date | Jun 19, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D211/90
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process is provided for producing diastereoisomer A or a pharmaceutically acceptable acid addition salt of 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(1-benzylpyrrolidin-3-yl) ester 5-methyl ester which comprises subjecting a mixture of diastereoisomers A and B of 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-(1-benzylpyrrolidin-3-yl) ester 5-methyl ester to column chromatography using silica gel as a carrier and a mixture of ethyl acetate and acetic acid as an eluant, and then separating the acetate of diastereoisomer A from the eluate, or treating the acetate with a base, or further treating the resulting diastereoisomer A with a pharmaceutically acceptable acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.