天然产物(±)-Lupinine和(±)-Epilupinine的简便合成

Concise Synthesis of(±)-Lupinine and(±)-Epilupinine

羽扇豆碱和表羽扇豆碱是典型的喹诺里西啶类生物碱。以哌啶酸乙酯盐酸盐为原料,通过氮烷基化反应、迪克曼缩合反应、Krapcho脱羰反应、Wittig反应等4步反应制得关键中间体5,总产率46.7%。化合物5可经文献转化,完成(±)-lupinine和(±)-epilupinine的合成。该合成方法具有合成路线短,产率高以及操作简单等优点。

Lupine and epilupine are typical quinolizidine alkaloids.Using ethyl piperidinate hydrochloride as raw material,we first synthesized the key intermediate 5 through four steps,including N-alkylation reaction,Dickman condensation,Krapcho decarbonylation reaction,Wittig reaction,and the total yield of the four steps was 46.7%.The formal total synthesis of(±)-lupine and(±)-epilupine could be completed via borohydride oxidation of compound 5 according to the reference method.At the same time,the synthetic method has reference significance for the synthesis of complex alkaloid molecules containing the similar nitrogen heterocyclic system.