Chemical Study of Alkaloids in Tropical Medicinal Plants as the Lead-Compounds to Develop New Biologically Functional Molecules.

1.泰国和马来土著人在热带地区使用Mitragyna speciosa Korth.的叶子作为鸦片替代品。重新调查的生物碱成分的植物在马来西亚导致四个新的吲哚生物碱的分离，其不寻常的结构被阐明的全合成和/或光谱分析。本文研究了手性全合成少数几种Mitragyna生物碱的新的手性策略。一个有效的阿片激动特性的mitragynine和mitragynine pseudoindoxyl澄清在体外实验。Mitragynine pseudoindoxyl作用于μ-和δ-阿片受体，其激动效力是吗啡的20-50倍。2.为了建立新的Sarpagine型Hunteria生物碱的合成路线，进行了模型实验，通过自由基环化策略合成了单萜吲哚生物碱Geissocelline。3.从泰国乌檀中分离得到7个吲哚类化合物和2个吲哚类化合物。10-合成了羟基异柳胺及其五乙酰基衍生物，考察了其C3立体化学。

1.The leaves of Mitragyna speciosa Korth.have been known as an opium substitute in troditional use by Thai and Malay natives. Reinvestigation of the alkaloidal constituents of the plant in Malaysia resulted in the isolation of four new indole alkaloids, whose unusual structures were elucidated by total synthesis and/or spectroscopic analysis. New synthtic strategy for the chiral total syntheses of minor Mitragyna alkaloids was studied. A potent opioid agonistic property of mitragynine and mitragynine pseudoindoxyl was clarified in vitro experiments. Mitragynine pseudoindoxyl, whose agonistic potency is 20-50 fold greater than that of morphine, acts on mu-and delta-opioid receptors.2.To establish the synthetic route of new Sarpagine-type Hunteria alkaloids, a model experiment was done, through which a monoterpenoid indole alkaloid, geissoschizine, was synthesized via radical cyclization strategy. Inhibitory effects of corymine, an alkaloidal component from Hunteria zeylanica, on glycine receptors was found.3.From Nauclea orientalis in Thailand, seven non-alkaloidal and two glycosidic indole compounds were isolated. 10-Hydroxystrictosamide and its pentaacetyl derivative were prepared to examne the C3 stereochemistry.