STEREOSELECTIVE SYNTHESIS OF OLIGO-TETRAHYDROFURANS

The present review covers synthetic work accomplished in the oligotetr ahydrofuran (oligo-THF) area between 1986 and July 1994. Oligo-THFs ar e key structural elements in the Annonaceous acetogenins, natural prod ucts with interesting biological and pharmacological activities. Nonna tural oligo-THFs possess potential applications in the field of ion bi nding (THF-podands) and ion transport (membrane bound ion channels mad e out of oligo-THFs). Described here is the current synthetic methodol ogy to obtain oligo-THFs in a stereocontrolled manner. Emphasis is mad e on two approaches: intramolecular epoxide opening (epoxide-cyclizati on cascades) and intramolecular ether formation (multiple Williamson r eactions).