桃金娘叶的化学成分研究

Chemical Constituents from Leaves of Rhodomyrtus tomentosa

摘要:

为了解桃金娘[Rhodomyrtus tomentosa (Ait.) Hassk.]的化学成分,从其叶的醇提物中分离得到10 个化合物,经波谱分析分别鉴定为羽扇豆醇 (1)、杨梅素-3-O-α-L-鼠李糖苷 (2)、rhodomyrtone (3)、4,8,9,10-四羟基-2,3,7-三甲氧基蒽醌-6-O-β-D-葡萄糖苷 (4)、豆甾醇 (5)、山奈酚-3-O-α-L-呋喃阿拉伯糖苷 (6)、杨梅素 (7)、23-羟基委陵菜酸 (8)、2α,3β,19α,23-四羟基乌苏-12-烯-28-酸28-O-β-D-吡喃葡萄糖苷 (9)和laricitrin (10)。其中化合物5~10 均为首次从桃金娘中分离得到。化合物3 对金黄色葡萄球菌、蜡样芽孢杆菌和枯草芽孢杆菌表现出显著的抗菌活性(MIC=0.78 μg mL^-1)。

Abstract:

In order to understand the chemical constituents of Rhodomyrtus tomentosa (Ait.) Hassk., ten compounds were isolated from alcohol extract of R. tomentosa leaves. On the basis of spectral data, they were identified as: lupeol (1), myricetin-3-O-α-L-rhamnoside (2), rhodomyrtone (3), 4,8,9,10-tetrahydroxy-2,3,7-trimethoxyanthracene- 6-O-β-D-glucopyranoside (4), stigmasterol (5), kaempferol-3-O-α-L-furanoarabinoside (6), myricetin (7), 23-hydroxytormentic acid (8), 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid β-D-glucopyranosyl ester (9) and laricitrin (10). Compounds 5-10 were obtained from this plant for the first time. Compound 3 showed antibacterial activity against Staphylococcus aureus, Bacillus cereus and B. subtilis with MIC=0.78 μg mL^-1.