CYTOTOXIC STUDIES AND IN VITRO EFFECTS OFTRANS-3,4,4’,5-TETRAMETHOXYSTILBENE, A BIOACTIVE COMPOUND ISOLATED FROM LONCHOCARPUS PUNCTATUS KUNTH

Abstract

the bioassay-guided fractionation of Lonchocarpus punctatus inflorescence extracts led to the purification of the trans (1) and cis (2) isomers of 3,5-dimethoxystilbene, trans-3,4,4’,5-tetramethoxystilbene (3), 4,4’,6’-trimethoxychalcone (4) and 5hydroxy-7,4’-dimethoxyflavone (5) as their main constituents. the structures of the compounds were established by comparing their nuclear magnetic resonance and mass spectrometry data with that from the literature. among these metabolites, trans-3,4,4’,5-tetramethoxystilbene (3) exhibited potent cytotoxic activity against luminal a (cc₅₀ = 2.2 µM), HEr2 (cc₅₀ = 1.1 µM) and basal triple negative (cc₅₀ = 1.8 µM) breast cancer cell lines, but no cytotoxic effects were observed against immortalized hepatocyte cell lines (cc₅₀ > 50 µM), and medium (CYP3A4, CYP2C9) and low (CYP2D6) inhibitory properties were observed for P450 isoforms.