Chemical constituents and bioactive activities of Eleutherine americana / 中草药

ABSTRACT

Objective: To study the chemical constituents of Eleutherine americana. Methods: The compounds were isolated by various chromatographic techniques, including silica gel, TLC, sephadex LH-20, and semi-preparative HPLC, and their structures were identified by their physicochemical properties and 1H-NMR and 13C-NMR data. Results: Fifteen compounds were isolated from E. americana, which were germacrenin B (1), phaffiaol (2), 4,8-dihydroxy-3-methoxy-l-methylonthra-9,10-quinone-2-carboxylic acid methyl ester (3), 3-heptadecyl-5-methoxyphenol (4), ethyl linoleate (5), 3,5-dimethoxybiphenyl-4’-ol (6), karwinaphthol A (7), 5-hydroxylkarwinaphthol A (8), 3,4-dimethoxy-8-hydroxy-1-methyl-anthra-9,10-quinone-2-carboxylic acid methyl ester (9), isoeleutherin (10), eleutherin (11), isoeleutherol (12), naphtho-γ-lactone (+)-9-hydroxyeleutherol (13), senkyunone (14), and palmitoleic acid (15). Conclusion: Compounds 2, 4-7, and 13-15 were isolated from the genus for the first time. The compounds 3, 8, and 13 had strong vasodilator effects with diastolic rate of 85.3%, 81.8%, and 89.5%, respectively, which were basically equivalent to the positive drug of tanshinone IIA (86.3%).