Structures of cytotoxic bicyclic hexapeptides, RA-XIX, -XX, -XXI, and -XXII, from Rubia cordifolia L.
作者:Ji-Ean Lee、Yukio Hitotsuyanagi、Koichi Takeya
DOI:10.1016/j.tet.2008.01.094
日期:2008.4
Novel bicyclic hexapeptides, RA-XIX, -XX, -XXI, and -XXII, were isolated from the roots of Rubia cordifolia L. The structures of RA-XIX and RA-XX were established by semisynthesis from a cycloisodityrosine, derived from previously reported RA-VII, and those of RA-XXI and RA-XXII by chemical correlation with RA-XX and previously reported RA-VIII, respectively. The IC50 values of these new peptides against
从茜草的根中分离出新颖的双环六肽RA-XIX,-XX,-XXI和-XXII。RA -XIX和RA-XX的结构是通过半合成从环异二酪氨酸衍生而来的,该化合物来自先前的报道RA-VII,RA-XXI和RA-XXII分别通过与RA-XX和先前报道的RA-VIII的化学相关性分析。这些新肽对P-388白血病细胞的IC 50值为0.013-0.63μg/ mL。