Synthesis of the Tetronate-Containing Core Structure of the Antibiotic Abyssomicin C

Abstract

S y n t h e s i s o f t h e A b y s s o m i c i n C o r e S t r u c t u r eAbstract: The core structure of abyssomicin C (1) containing an oxabicyclooctanone ring and a tetronate was prepared from the addition product of lithium ethyl propiolate and 4-tert-butyldimethylsilyloxycyclohexanone. Tetronate formation via addition of sodium methanolate followed by hydrolysis gave the hydroxy tetronic acid 27. The spiro compound 27 could be cyclized to the tricyclic tetronate 23 by a transannular Mitsunobu lactonization. Alternatively, 27 could be prepared from the cyanohydrin cis-19.