PROCESS FOR PRODUCING N-DESMETHYLVINBLASTINE, VINCRISTINE, N-DESMETHYLLEUROSINE, H-DIMETHYL-N-FORMYLLEUROSINE, N-DISMETHYL-N-(ETHOXYMETHYL)-VINBLASTINE, N-DESMETHYL-N-(ETHOXYMETHYL)-LEUROSINE OR THEIR SALTS

摘要

A process for the preparation of diindolealkaloids, especially new compounds corresponding to vinblastine or leurosine, in which the N-methyl group is replaced by an N-CH2-OC2H5 group having antitumor properties. The starting compounds are subjected to oxidation by chromic acid or an alkali metal dichromate at temperatures from -90 DEG C. to -30 DEG C. but preferably below about -45 DEG C. when the new compounds are to be produced, ethanol being present in this case.