Research of Bioactive Alkaloids with Polycyclic Skeletons

点击翻译按钮获取中文摘要

The Lycopodium and Daphniphyllum alkaloids represent a large family of plant constituents obtained from the club moss belonging to Lycopodiaceae and trees of the genus Daphniphyllum (Daphniphyllaceae), respectively. These structurally diverse alkaloids often possess unusual skeletons, and many of them continue to be of interest from biogenetic and biological points of view as well as providing challenging targets for total synthesis.Investigation on extracts of Lycopodium complanatum and L. obscurum (Lycopodiaceae) resulted in the isolation of new alkaloids, complanadine B, lycopladine A, and obscurumines. Lannotinidines isolated from L. annotinum and L. annotinum var. acrifolium showed elevated activity of NGF biosynthesis. Lycopodatines and lycovatine A were isolated from L. inundatum and L. clavatum var. Robustum, respectively. Lycoperine A which showed inhibition of acetylcholinesterase and nankakurine B were isolated from L. hamiltonii and structure of nankakurine A was revised. S … More ome of these new alkaloids showed some effects on neurotrophic factor biosynthesis.Daphniphyllum alkaloids are a family of fused-heterocyclic natural products elaborated by trees of the genus Daphniphyllum (Daphniphyllaceae). These ring systems have attracted great interest as challenging targets for total synthesis^3 as well as biosynthetic studies. In our search for structurally unique and biogenetically interesting Daphniphyllum alkaloids, two novel fused-pentacyclic alkaloids, daphmanidins C and D, consisting of an 1-azabicyclo[5.2.2]undecane, a hexahydronaphthalen-l-one, and a cyclopentane rings, and daphtenidines A-D were isolated from the leaves of Daphniphyllum teijismanni. Daphmanidins C and D induced secretion of neurotrophic factors from human astrocytoma cells.Two new taxoids, taxezopidines M and N, have been isolated from seeds of the Japanese yew Taxus cuspidata Sieb. et Zucc. and the structures were elucidated on the basis of spectroscopic data. Taxezopidine M reduced the depolymerization process at higher concentration. Less