Process for an enantioselective synthesis of optically active 14-oxo-E-homo-eburnane derivatives
US4399069A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1981 |
| Grant date | Aug 16, 1983 |
| Priority date | — |
| Expiry date | Oct 16, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D471/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a new enantioselective synthesis for the preparation of optically active 14-oxo-E-homo-eburnane derivatives of the formula (Ia) ##STR1## wherein R.sup.1 is alkyl having from 1 to 4 carbon atom. In the synthesis optically active 6-alkoxycarbonylhexahydroindoloquinolizinium salts are employed as starting materials, which contain a center of chirality at the site of attachment of the carboxyl group. This center of chirality preserves the optical activity of the optically active tryptophan ester from which this compound has been prepared until a new center of chirality is formed in the molecule in a configuration corresponding to the desired end product. The carboxyl group, which is not needed in the end product and only serves to preserving the optical activity can then be eliminated. Compounds of the formula (Ia) are known in the art and may be used in the synthesis of (+)-vincamine and (+)-apovincaminic acid ethylester.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.