Chiral syntheses of the antibiotics anisomycin and pentenomycin from carbohydrates

Abstract

Syntheses of the natural, optically active forms of the antibiotics anisomycin and pentenomycin are described using simple glucose derivatives as chiral starting materials. The key step in the synthesis of anisomycin is the formation of a pyrrolidine ring embodying all three of the desired asymmetric centers via intramolecular nucleophilic displacement of a 3-Q-tosyl function in an-;ppropriately substituted 6-amino-6deoxy--~-talofuranose derivative. Further elaboration involves the liberation of an aldehyde group by periodate oxidation of the 1,2-diol, Grignard coupling and removal of extraneous functions and blocking groups by several reductive steps.