Olefinically unsaturated substituents at C-11 of steroid cyclization precursors
US4064185A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1975 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Apr 28, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2601/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Compositions are provided as well as methods for preparing the compositions which serve as cyclization precursors for the preparation of C-11 alkenyl substituted steroids and nor-steroids. The alkenyl group may be converted after cyclization to a variety of heterosubstituents to provide heterofunctionalized C-11 steroids and nor-steroids. The compounds are provided having an initiator group, which has a chalcoxy atom in juxtaposition to a double bond, an olefinically unsaturated linking group and a terminating group which acts to from a carbocation which reacts with a nucleophile to provide a stable product. The C-11 substituent is found to provide upon cyclization the alpha-configuration, so that the subject compounds provide a direct route to the difficultly accessible alpha-C-11 substituted steroids, or, if desired, the alpha-configuration can be inverted to the beta-configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.