Two cyclopeptides, celogentin L(1) and its epimer lyciumin A(2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1 D-, 2...Two cyclopeptides, celogentin L(1) and its epimer lyciumin A(2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1 D-, 2 D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2 D-NMR and comparison of the experimental and calculated electronic circular dichroism(ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma Hep G2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.81322051 and 31400300)the Natural Science Foundation of Jiangsu Province(No.BK20151442)the Project Funded by the Priority Academic Program Development(PAPD) of Jiangsu Higher Education Institutions
文摘Two cyclopeptides, celogentin L(1) and its epimer lyciumin A(2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1 D-, 2 D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2 D-NMR and comparison of the experimental and calculated electronic circular dichroism(ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma Hep G2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.
