New acetylated terpenoids from sponge rhabdastrella providentiae inhibit no production in LPS stimulated BV2 cells

Abstract

Three new acetylated terpenoids, rhabdaprovidines A-C (1-3), were isolated from the Vietnamese sponge Rhabdastrella providentiae. Their chemical structures were established by HR-ESI-MS, 1D and 2D-NMR experiments. These compounds share 6,6,5-tricyclic nucleus of isomalabaricane-type triterpene, the specific secondary constituents from Rhabdastrella species. Compounds 1-3 inhibited NO production in LPS stimulated BV2 cells with IC50 values of 20.4 ± 1.5, 17.5 ± 0.9, and 46.8 ± 2.3 μM, respectively.