Sarsolenane and Capnosane Diterpenes from the Hainan Soft Coral <i>Sarcophyton trocheliophorum </i>Marenzeller as PTP1B Inhibitors

Abstract

Abstract Two new sarsolenane diterpenes, dihydrosarsolenone ( 2 ), methyl dihydrosarsolenoneate ( 3 ), and two new capnosane diterpenes, sarsolilides B ( 5 ) and C ( 6 ), were isolated together with the known analogue, sarsolilide A ( 4 ), from the Hainan soft coral Sarcophyton trocheliophorum Marenzeller. Their structures were elucidated by detailed spectroscopic analysis and by comparison with reported data, leading to a structure revision of sarsolenone ( 1 ). The absolute configurations of 2 and 5 were determined by TDDFT ECD calculations, and they could be used as ECD reference compounds in the determination of the absolute configuration of their related derivatives. Compounds 4 and 5 exhibited inhibitory activity in vitro against protein tyrosine phosphatases 1B (PTP1B), representing the first report of PTP1B inhibitory activity for capnosane diterpenes.