2. Academic Validation
  3. A pair of cyclopeptide epimers from the seeds of Celosia argentea

A pair of cyclopeptide epimers from the seeds of Celosia argentea

  • Chin J Nat Med. 2018 Jan;16(1):63-69. doi: 10.1016/S1875-5364(18)30030-X.
Feng-Jie Liu 1,  Zhi-Hua Zhu 2,  Yan Jiang 3,  Hui-Jun Li 4
Affiliations

Affiliations

  • 1 State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
  • 2 Anhui Medical College, Hefei 230601, China.
  • 3 School of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China. Electronic address: [email protected].
  • 4 State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China. Electronic address: [email protected].
PMID: 29425591 DOI: 10.1016/S1875-5364(18)30030-X
Abstract

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 1D-, 2D-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 2D-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 HepG2, 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.

Keywords

Absolute configuration; Celogentin L; Celosia argentea; Cyclopeptides; Lyciumin A.

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