Rhabdastrellic Acid-A, a Novel Triterpenoid from the Marine Sponge <i>Rhabdastrella globostellata</i>

Abstract

A new isomalabaricane triterpenoid, rhabdastrellic acid-A (1), was isolated from the sponge Rhabdastrella globostellata (Carter) collected from the South China Sea near Hainan Island, People's Republic of China. Its structure was established on the basis of UV, IR, MS, 1H-NMR, 13C-NMR, and 2D NMR spectrometry. The relative and absolute stereochemistries were solved by NOESY and CD studies, respectively.