54 ヤエヤマシキミの新規セスキテルペノイドの構造(ポスター発表の部)

概要

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New type of sesquiterpenes, isodunniannin (1), illicinolides A (2) and B (3), and tashironin (4), and tricyclic prenylated C_6-C_3 compound, tricycloillicinone (5) have been isolated from the dried woods of Illicium tashiroi which were collected in Ishigaki Island. Compounds 2, 3, and 4 belong to a unique class of sesquiterpenes biogenetically closely related to anisatin and pseudoanisatin. On the other hand, compound 5 is the first example of tricyclic prenylated C_6-C_3 compound, which is presumably derived from the illicinons occurred in the title plant. The structure of isodunnianin (1) was determined by the analyses of the 2 D NMR data and comparison of its ^<13>C NMR data with those of an analogue, dunniannin (6). The structure of Illicinolide A (2) was established by X-ray analysis of the p-bromobenozoyl derivative (2a) whereas illicinolide B (3) was assigned the structure as 9α-hydroxyillicinolide A by comparing spectral data with those of 2. The structures for tashironin (4) and tricycloillicinone (5) were elucidated mainly on the basis of the extensive 2 D NMR analyses, in particular, HMBC and NOE. Among the compounds isolated in this study, only isodunnianin enhanced not only neurite outgrowth but also choline acetyltransferase activity at 10^<-5> M in primary neuronal cell culture of fetal rat cerebral hemisphere.
天然有機化合物討論会の論文
1992-09-10