Preparation of vincadifformine and related derivatives
US4283536A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 30, 1979 |
| Grant date | Aug 11, 1981 |
| Priority date | — |
| Expiry date | Apr 30, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D487/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
This invention relates to the preparation of vincadifformine and related derivatives which are useful as starting material for the synthesis of among other alkaloids vincamine and other similar compounds possessing interesting psychopharmacologic properties. A tetrahydro-.beta.-carboline (II) is reacted with benzoyl chloride to provide a 2-benzoyl-1,2,3,4-tetrahydro-9H-pyrido-(3,4-b)-indole (III). Then compound (III) is reduced to give a 2-benzyl-1,2,3,4-tetrahydro-9H-pyrido-(3,4-b)-indole (IV). Thereafter, compound (IV) is transformed by t-butyl hypochlorite into a chloroindolenine derivative (V) which is immediately treated with a metal dialkylmalonate such as thallium t-butyl methyl malonate to give a dialkyl 3-benzyl-1,2,3,4,5,6-hexahydroazepino-(4,5-b)-indole-5,5-dicarboxylate (VI). Compound (VI) is then partly decarboxylated into a alkyl 3-benzyl-1,2,3,4,5,6-hexahydro-(4,5-b) indole-5-carboxylate (VII). Compound (VII) is hydrogenated to give an alkyl 1,2,3,4,5,6-hexahydroazepino-(4,5-b)-indole 5-carboxylate (VIII). In an alternative embodiment, compound (VI) can be hydrogenated to the corresponding dialkyl 1,2,3,4,5,6-hexahydroazepino-(4,5-b)-indole-5,5-dicarboxylate which is…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.