Stereoselective syntheses of 2,5-disubstituted hydroxyfuan derivatives as synthon of polyether antibiotics

摘要

Stereoselective synthesis of optically active 2,5-dialkyltetrahydrofurans (8), (11) and (12), which correspond to a central moiety of pamamycin 607, have been achieved on the baiss of lactone-ring transformation via a phenonium ion, intramolecular Friedel-Crafts reaction, oxidative decomposition of an aromatic ring and differentiation of two ester groups by a chemical or chemo-enzymatic method.