First Enantiospecific Synthesis of the Antitumor Marine Sponge Metabolite (−)-15-Oxopuupehenol from (−)-Sclareol
摘要:
[GRAPHICS]A new route toward puupehenone-related bioactive metabolites from (-)-sclareol, based on the palladium(II)-mediated diastereoselective cyclization of a drimenylphenol, is described. Utilizing this, the first enantiospecific synthesis of the antitumor and antimalarial (-)-15-oxopuupehenol, together with improved syntheses of (+)-puupehenone, (+)-puupehedione, and (+)-15-cyanopuupehenone, were accomplished.
Enantiospecific synthesis of (+)-puupehenone from (−)-sclareol and protocatechualdehyde
摘要:
The first enantiospecific synthesis of the antitumor and cholesteryl ester transfer protein (CETP) inhibitor (+)-puupehenone (19) from (-)-sclareol (10) and protocatechualdehyde (4) is described. The key steps of the reaction sequence are the organoselenium-induced cyclization of the mixture of regioisomers 15a-b to give 16 and 17, with complete diastereoselectivity, and the simultaneous removal of benzyl and phenylselenyl groups of 16 and 17 by treating with Raney Ni. (C) 1997 Elsevier Science Ltd.