Alkinyl terminating groups in biogenetic-like cyclizations to steroids
US4189431A · kind A · utility
6Cited by
2References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1977 |
| Grant date | Feb 19, 1980 |
| Priority date | — |
| Expiry date | Aug 3, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2601/16
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Polyenine compounds are provided having the naturally occurring geometry and a group which in the presence of acid initiates a carbocation cyclization to a steroid or A-nor-steroid structure, particularly the pregnane parent structure. The compounds are formed for the most part by condensation of two units prepared from readily available small molecules and are joined to form a polyenine, usually having a substituted carbocyclic ring which upon contact with a Lewis acid catalyst (includes protonic) cyclizes directly to provide the 5-membered D ring as well as substitution at the C-20 position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.