Chemical constituents from the roots of Morinda talmyi (Rubiaceae)

Phytochemical investigation of the roots of Morinda talmyi (Pit.) Chantar. led to the isolation of eleven compounds. They consist of two previously undescribed anthraquinones, 3-hydroxy-1,2,5-trimethoxy-6-methylanthraquinone (1) and damnacanthol acetate (2), together with nine known compounds: 1-hydroxy-2-methyl-9,10-anthraquinone (3), soranjidiol (4), morindone (5), nordamnacanthal (6), lucidin (7), lucidin ω-methyl ether (8) lucidin ω-ethyl ether (9), damnacanthol (10) and lucidin 3-O-β-primeveroside (11). The structures of the isolated compounds were elucidated by thorough analysis of spectroscopic (IR, NMR) and spectrometric (MS) data. Compounds 1 and 2 were tested against eight bacterial strains. Only compound 2 exhibited weak activity against methicillin-resistant Staphylococcus aureus and Staphylococcus aureus (MIC = 128 µg/ml). This is the first phytochemical investigation of M. talmyi.