Secondary metabolites from the stem barks of rhizophora mucronata Lam.

Abstract

Using various chromatographic separations, three phenolic derivatives (1‒3) and three phytosteryl glycosides (4-6) were isolated from a methanolic extract of R. mucronata Lam. stem barks. Their structures were elucidated to be cinchonain Ib (1), breynioside B (2), polystachyol (3), β-sitosterol 3-O-β-D-glucopyranoside (4), β-sitosterol 3-O-β-D-(6'-O-palmitoyl) glucopyranoside (5), and β-sitosterol 3-O-β-D-(6'-O-stearoyl)glucopyranoside (6) by detailed analysis via spectroscopic techniques (1D, 2D NMR, and ESI-MS data) as well as comparison with those reported. This is the first report of compounds 1-6 from the Rhizophora genus.