【摘要】 1.重研究了国产钩吻生物碱,比较和改良这些生物碱的提取方法.除获得前人曾经报告的钩吻素子、钩吻素卯和钩吻素甲以外,还得到了两种新的次要生物碱,钩吻素丁和钩吻素戊,但未得钩吻素丙和钩吻素辰.钩吻素丁熔点232-234°,实验式暂定为C₂₆H₃₀N₂O₄;钩吻素戊熔点202-204°,实验式暂定为C₁₉H₂₂N₂O;从紫外光谱推断,二者都是吲哚类型的生物碱.并修正钩吻素卯的实验式为C₂₀H₂₆N₂O₄,从紫外及红外光谱初步推测,它可能是一种内盐式的假吲哚类型生物碱. 2.对国产钩吻中的主要生物碱钩吻素子的化学结构作了初步解析.从光谱及化学证据推断,钩吻素子与钩吻素甲具不同的发色系统,前者属于假吲哚型,而后者已知是属于2-氧吲哚型的.虽然这两种生物碱都含环外乙烯基,N_b-甲基及可能具环醚结构,但是其脂环部分的构造按推断亦不相同.更多还原

【Abstract】 1. The alkaloid contents of Chinese gelsemium （G. elegans Benth.） have been reinvestigated. Various procedures of isolation of the alkaloids were compared and a more efficient one developed. The present authors isolated besides previously reported koumine,kouminidine and gelsemine two new minor alkaloids:koumicine, m. p. 232-4°and koumidine, m. p.202-4°.However, sempervirine and kounidine were not obtained.Empirical formulae C₂6H₃0N₂O₄ and C₁9H₂2N₂O are provisionally assigned to koumicine and koumidine, respectively, and spectral evidences indicate that both these alkaloids are of indole type. The unconventional formula of kouminidine, C₁9H₂5O₄N₂, is revised to C₂0H₂6N₂O₄.Preliminary considerations based on UV and IR spectra suggest that kouminidine is possibly an indolenine type alkaloid with a zwitterionic structure.2. The constitution of koumine, the main alkaloid of Kou-Wen, has been preliminarily studied on spectral as well as on chemical ground. It is proposed that, in contrast to gelsemine, koumine probably possesses a pseudoindole ring system. Although gelsemine and koumine both contain an exo-vinyl, an Nb-methyl and most likely a cyclic ether linkage, the structures of the alicyclic parts of these two alkaloids appear also different from each other.更多还原