文摘
Total syntheses of omphadiol and pyxidatol C, two isomeric africanane sesquiterpenes sharing identical 5-7-3 tricyclic carbon skeletons yet containing distinct oxidation patterns, are reported. The trans-fused 5,7-carbocycles in the terpenoids characterized by specific oxidation patterns were derived from a readily available cis-fused 5,7-carbocyclic common intermediate.