Superacidic cyclization of higher terpenoid acids and their esters
摘要:
The superacidic cyclization of aliphatic and partially cyclized C-15-C-25 terpenoid acids and their esters proceeds structure-selectively and stereospecifically, affording a-isomers of completely cyclized epimeric beta,gamma-unsaturated acids of esters; the configuration of their carboxylic or ester groups is predetermined by the configuration of the double bond conjugated with the carboxyl or ester groups in the starting compounds.