驱蛔药川楝皮及苦楝皮中异川楝素的分子结构

从四川川楝和广西苦楝树皮中分到一个新化合物,分子式C₃₀H₃₈O₁₁,是川楝素同分异构体,名异川楝素。经化学和光谱等测定结构为(2)式,即1α,7α-二羟基-3α,12α-二乙酰氧基-11,15双酮基-19,28半缩醛基-17α-(3)-呋喃三萜。

THE STRUCTURE OF ISO-CHUANLIANSU ISOLATED FROM CHINESE MEDICINE-THE BARK OF MELIA

Iso-Chuanliansu (2), a new constituent, was isolated from Chinese medicine-the bark of Melia toosendan in the province of Sichuan and Melia azedarach in the province of Guangxi. The decoction of the bark of Melia has been used as anthelmintic against ascaris among the people for generations. The molecular formula of iso-Chuanliansu (2) is C₃OH₃₈O₁₁, the same as Chuanliansu (1). It is also a β-substituted furanoid triterpene. The difference between Chuanliansu(1) and iso-Chuanliansu(2) resides only in ring D. The 14β, 15β epoxide group in the former is replaced by a carbonyl group situated at the 15 position in the latter. It is proved by the fact that when Chuanliansu(1) was treated with mineral acid, it could be transformed into iso-Chuanliansu (2) smoothly. The CD curve of iso-chuanliansu(2), similar to that of Amoorastatone (5), showed negative cotton effect at 298, 309 and 316 nm, so that the stereo-pattern may be shown as formula(2). It is a 1α, 7α-dihydroxy-3α, 12α-diacetoxy-11, 15dioxo-19β, 28β-acetal-meliacan.