番荔枝中的一对环肽构象异构体
Two Conformational Isomers of a Cyclopeptide from Annona squamosa
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摘要: 前报从番荔枝(Annona squamosa)的种子中分离得一个新的环肽squaminA(cyclo-〔l-prolyl-l-(S-oxo)-methionyl-l-tyrosyl-l-glycyl-l-valyl-l-alanyl-l-isoleucy1〕,1)。进一步对番荔枝种子进行研究,发现另一个环肽,命名为squaminB(2),用2DNMR,FAB-MS和氨基酸分析,证明2的平面结构1一Abstract: A novel cyclopeptide, squamin A(cyclo l -prolyl- l-(S -oxo)-methionyl- l -tyrosyl- l -glycyl- l -threonyl- l -valyl- l -alanyl- l -alanyl- l -isoleucyl was isolated from \%Annona squamosa\%. Another cyclopeptide, squamin B, a conformat