A new triterpenoid (1) and four known compounds (2–5) were isolated from Gymnema sylvestre. The structure of compound 1 was elucidated as (3β,16β,22α)-22-benzoyloxy-16,23,28,29-tetrahydroxyolean-12-en-3-yl-O-β-D-glucopyranosiduronic acid by spectroscopic data (¹H, ¹³C NMR, HMBC, HSQC, COSY, and NOESY). Additionally, compound 1 presented allelopathic activity on the growth of lettuce at 100 μM.

中文翻译：

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匙羹藤新三萜类化合物及其化感活性

从匙羹藤中分离出一种新的三萜类化合物( 1 ) 和四种已知化合物( 2-5 ) 。化合物1的结构被阐明为(3β , 16β , 22α ) -22-苯甲酰氧基-16,23,28,29-四羟基齐墩果酸-12-en-3-基-O-β-D-吡喃葡萄糖醛酸光谱数据（¹ H、¹³ C NMR、HMBC、HSQC、COSY 和 NOESY）。此外，化合物1在 100 μM 浓度下对生菜生长具有化感作用。