ABSTRACT
A phytochemical investigation of the leaves of Vitex quinata (Lour.) F.N. Williams (Verbenaceae), guided by the MCF-7 human breast cancer cell line, led to the isolation of a new δ-truxinate derivative (1) and a new phytonoic acid derivative (2), together with 12 known compounds. The structures of the new compounds were determined by spectroscopic methods as dimethyl 3,4,3',4'-tetrahydroxy-δ-truxinate (1) and methyl 10R-methoxy-12-oxo-9(13),16E-phytodienoate (2), respectively. In a cytotoxicity assay, (S)-5-hydroxy-7,4'-dimethoxyflavanone (3) was found to be the sole active principle, with ED(50) values of 1.1-6.7 µM, respectively, when tested against a panel of three human cancer cells. Methyl 3,4,5-O-tricaffeoyl quinate (4) showed activity in an enzyme-based ELISA NF-κB p65 assay, with an ED(50) value of 10.3 µM.
ABSTRACT
Activity-guided fractionation of a CHCl(3)-soluble extract of the twigs of Aglaia rubiginosa, using human oral epidermoid carcinoma (KB) cells as a monitor, led to the isolation of a new naturally occurring cyclopenta[b]benzofuran, 1-O-acetylrocaglaol (1), along with seven known compounds, methyl rocaglate (2), rocagloic acid (3), 1-O-acetylmethyl rocaglate (4), desyclamide, eryodictiol, 5-hydroxy-3,7,4'-trimethoxyflavone, and naringenin. A CHCl(3) extract of the leaves of A. rubiginosa yielded the new compound (3S,4R,22R)-cholest-7,24-diene-3,4,22-triol (5), as well as 11 known compounds, including 2 and 4 and cabraleone, dammarelonic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid methyl ester, (3beta,4beta,22R)-ergosta-5,24(24')-diene-3,4,22-triol, ocotillone, shoreic acid, beta-sitosterol, and beta-sitosterol glycoside. The structures of 1 and 5 were elucidated by spectral and chemical methods. Isolates were evaluated with a human cancer cell panel, and compounds 1-4 were found to exhibit potent cytotoxic activity.
