Total synthesis of (±)-gleenol and (±)-axenol via a functionalized spiro[4.5]decane

Abstract

Total synthesis of the biologically important axane sesquiterpenes, gleenol (1) and axenol (2), was accomplished through a readily available spiro[4.5]decane. The key features of the synthesis of 1 and 2 include Claisen rearrangement to afford the multi-functionalized spiro[4.5]decane 4 as a single diastereomer in excellent yield, installation of the C7 isopropyl group via ketene dithioacetal instead of direct alkylation and a diastereoselective reduction of ketone under the Birch conditions. © 2007 Pharmaceutical Society of Japan.