川楝素(Toosendanin)为四环三萜类化合物(Ⅰ)[钟炽昌等:化学学报 1975,33:35;李培忠等:中草药1982,(6):28],系由川楝树皮提取而得,具有抗肉毒中毒作用。但由于该化合物毒性较大,化疗指数低,影响临床应用,故对其结构进行了化学改造,以力求降低毒性,提高效价。我们曾先后用硼氢化钾(钠)、四氢锂铝还原C环上的羰基为羟基,但均未奏效。由于该化合物在碱性条件下反 Toosendanin is a tetracyclic triterpene compound (I) [Zhong Chi Chang et al: Acta J Chem. 1975,33: 35; Li Peizhong et al .: Chinese herbal medicine 1982, (6): 28] , With anti-botulism effect. However, due to the toxicity of the compound, low chemotherapy index, affecting clinical applications, so the chemical modification of its structure, in an effort to reduce toxicity and improve potency. We have with potassium borohydride (sodium), lithium aluminum tetrahydrochloride reduction C ring hydroxyl, but none worked. Since the compound is reversed under basic conditions