The precursor for (-)-a-multistriatin (alkyl 2,3,4-trideoxy-2,4-di-C-methyl-a-D-Zyxo-hexopyranoside) may be approached from the corresponding isomeric 4-oxo-2-C-methyl-or 2-oxo-4-C-methylpyranosides by (a) methylenation followed by (b) hydrogenation. The yields in step a and stereocontrol in step b have been found to depend strongly on a number of factors including the protecting group for the C6 hydroxyl. For elaboration to the multistriatin skeleton, the glycosidic methoxyl is hydrolyzed under neutral conditions by using refluxing dimethoxyethane-water which avoids any epimerization of the C2 methyl group. The resulting glycose is treated with vinylmagnesium bromide, and the allylic alcohol obtained is oxidized with manganese dioxide. Exposure of the enone to hydrogen then leads directly to a-multistriatin.«-Multistriatin, a component of the aggregation pheromone of the elm bark beetle Scolytus multistriatis, was isolated, characterized, and synthesized in racemic form by Silverstein and co-workers.1 Using a route beginning
3': 3,4]pyrrolo[l,2-a] indole (4), containing the complete ring system of the mitomycin antitumour antibiotics, is formed in a single step from 2-(N-phenylformimidoyl)indole (2) by treatment of its sodium salt with methyl 2-bromopropenoate; the aziridine undergoes facile thermal ring-opening to an azomethine ylide which adds i n situ to dimethyl butynedioate in 1,3-dipolar fashion.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.