Friedelin and related compounds. Part IX. Pachysandiol-A and isomeric friedelane-2,3-diols
Abstract
Friedelane-2α,3β-diol (IV; R1= R2= H) has been obtained by two routes starting from friedelin (I) and from cerin, and shown to be identical with pachysandiol-A. Cerin is now shown to be 2α-hydroxyfriedelan-3-one (III; R1= H) and the derived acetate has been epimerised to 2β-acetoxyfriedelan-3-one (VII; R1= Ac). Friedelin has been converted into friedelane-2α,3α-diol (VIII; R1= H) and cerin into friedelane-2β,3β-diol (IX; R1= H).