Phenolic Compounds from Monomeria barbata

Abstract

A new 9,10-dihydrophenanthrene derivative, monbarbatain E (1), together with 10 known bibenzyl or phenanthrene derivatives, were isolated from the acetone extract of the rhizomes of Monomeria barbata Lindl. The new compound was identified as 4-O-[4″-(5′-hydroxy-3′,3″-dimethoxybibenzyl)]-1,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene on the basis of extensive spectroscopic investigations (HR-ESI-MS, 1D and 2D NMR). Compounds 1 and 2 were evaluated for their cytotoxic effects, and compounds 2–5 were tested for their antioxidant activities. Compounds 1 and 2 exhibited medium cytotoxic activity against HL-60 and Skov-3 cell lines. Compounds 2–5 showed significant DPPH radical scavenging activities.