Chemical Study on the Indole Alkaloids from Plant Tissue Cultures

由日本千叶大学、泰国朱拉隆功大学和德国美因茨大学联合开展的“植物组织培养中吲哚类生物碱的化学研究”的研究获得了蒙布修国际科学研究基金的资助，取得了许多成功的成果。采用植物细胞悬浮培养技术对三种原产吲哚类生物碱的药用植物进行了研究。水杨碱在蛇纹草细胞培养物中的生物转化。在生物碱生产培养基中，对投喂ajmaline的蛇尾草（R. serpentina）植物细胞悬浮培养物的甲醇提取物进行了分离，得到了4种新的吲哚类生物碱：raumacline、N_b-methylraumacline、19(S)-羟基-N_b-methylraumacline和6 α -hydroxyraumacline。这些结构首先通过光谱分析被阐明，并通过由ajmaline进行的仿生化学合成得到了明确的确定。这些新化合物是第一个在C15和C16位置之间具有反式关系的巨链型吲哚生物碱的例子。新吲哚类生物碱的分离与鉴定。从白毛竹细胞悬浮培养中分离出了3种新的单萜类吲哚类生物碱：水蛭碱、3-氧-14、15-脱氢hazinilam和11-羟基烟碱，但目前产量很低。结构解析和立体化学分析主要采用二维核磁共振技术进行。蜘蛛碱是一种具有十元内酯特征的全新结构类药物。钩藤细胞培养中生物碱成分的研究。从钩藤细胞培养物中未检测到生物碱成分

The joint research among Chiba University (Japan), Chulalongkorn University (Thailand) and Mainz University (Germany) supported by a grant under the Monbusho International Scientific Research brought about many successful results on the subject "The Chemical Study on the Indole Alkaloids from Plant Tissue Cultures".The technology of plant cell suspension cultures was employed for three medicinal plants originally producing the indole alkaloids.I. Biotransformation of Ajmaline in Plant Cell Cultures of Rauwolfia serpentina Benth.From the methanol extracts of the plant cell suspension cultures of R. serpentina, which have been cultivated in the alkaloid-production medium after feeding of ajmaline, four new indole alkaloids, raumacline, N_b-methylraumacline, 19(S)-hydroxy-N_b-methylraumacline, and 6alpha-hydroxyraumacline were isolated. These structures first elucidated by the spectroscopic analysis were unambiguously determined by the biomimetically chemical synthesis from ajmaline. These new compounds are the first examples of the macroline-type indole alkaloids having the trans relationship between the C15 and C16 positions.II. Isolation of Novel Indole Alkaloids from Cell Cultures of Aspidosperma quebracho blanco Schlecht.From the cell suspension cultures of A. quebracho blanco, three novel monoterpenoid indole alkaloids, aspidochibine, 3-oxo-14, 15-dehydrorhazinilam, and 11-hydroxytubotaiwine were isolated, though the production amounts of them were very low at this stage. The structure elucidation and the stereochemical analysis were made by mainly 2D NMR technique. Aspidochibine, bearing a characteristic ten membered lactone, is a completely new structural class of the quebrachamine series.III. Investigation of the Alkaloidal Components in the Cell Culture of Uncaria gambir.No alkaloidal constituent was detected from the cell cultures of Uncaria gambir