Tirucalla-5,24-dien-3 beta-ol [(13 alpha,14 beta,17 alpha,20S)-lanosta-5,24-dien-3 beta-ol] and three other Delta(5)-unsaturated tirucallanes from the roots of Bryonia dioica Jacq: The first naturally occurring C-10 methylated tetracyclic triterpene alcohols with a Delta(5)-monounsaturated skeleton

Four novel triterpene alcohols with a Delta(5)-unsaturated tirucallane-type skeleton, i.e. tirucall-5-en-3 beta-ol, tirucalla-5,24-dien-3 beta-ol, 24-methyltirucalla-5,24(24(1))-dien-3 beta-ol and (24S)-24-methyltirucalla-5,25-dien-3 beta-ol, have been isolated from the roots of Bryonia dioica Jacq. (Cucurbitaceae). The structures have been determined by spectroscopic and chromatographic methods. These compounds are the first examples of naturally occurring C-10 methylated triterpenes with a Delta 5-monounsaturated skeleton.