Phenolic constituents from Brainea insignis.

Phytochemical investigation on the methanol extract of Brainea insignis led to the isolation of 16 phenolic compounds, including an unusual flavanol coupled with phenylpropyl and shikimic acid units, brainicin (1), and a new flavonol acylglycosides brainoside B (2). The structures of new compounds were elucidated on the basis of extensive spectroscopic analysis. Compounds 1-5 were evaluated for their cytotoxic effects. However, none of the compounds showed significant cytotoxic activity against the HL-60, A549, SMMC-7721, MCF-7, SW480 cell lines (IC(50) > 40 microM).