Process for the preparation of vincaminic acid esters
US4464534A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1982 |
| Grant date | Aug 7, 1984 |
| Priority date | — |
| Expiry date | Sep 28, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D461/00
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a new process for the preparation of apovincaminic acid esters. More particularly, the invention concerns a process for preparing racemic and optionally active vincaminic acid esters of the formula (I) ##STR1## in which R.sup.1 and R.sup.2 independently stand for alkyl having from one to 6 carbon atoms, and 14-epimers thereof. According to the invention an octahydroindolo[2,3-a]quinolizine-oxime ester of the formula (II) ##STR2## in which R.sup.1 and R.sup.2 have the same meaning as defined above, is reacted with an aqueous solution of sulfurous acid or a salt thereof at a temperature of 80.degree. to 110.degree. C. and the 14-epimeric mixture obtained is epimerized or separated in a known manner and if desired, the racemic vincaminic acid esters are resolved. The valuable, pharmaceutically active compounds of the formula (I) can be prepared according to the invention in a considerably improved yield and the undesired side reactions can be suppressed and/or the by-products can easily be converted into other pharmaceutically active materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.