A pair of cyclopeptide epimers from the seeds of Celosia argentea / 中国天然药物

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.

A pair of cyclopeptide epimers from the seeds of Celosia argentea / 中国天然药物

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.

Chemical and cytotoxic constituents of Zanthoxylum nitidum / 中国中药杂志

Ten compounds were isolated from the methanol extract of Zanthoxylum nitidum through silica gel, Sephadex LH-20, RP-18 and HPLC chromatography techniques. Their structures were elucidated by the MS and NMR spectra as zanthonitidine B(1), cyclo-(Leu-Leu-Leu-Leu-Ile)(2),6S-10-O-demethylbocconoline(3), liriodenine(4), isoplatydesmine(5), 5, 5'-dimethoxylariciresinol(6), syringaresinol (7), episyringaresinol (8), marmesin (9) and syringaldehyde (10). Among them,1 is a new alkaloid,2 is a cyclopentapeptide isolated from plant kingdom for the first time, and 3 is from the genus Zanthoxylum for the first time. Compounds 3 and 4 exhibited cytoxoxicity against three human cancer cell lines HT29, A549 and MDA-MB-231 with IC₅₈ values of 27.37, 24.10, 33.58 μmol·L⁻¹ and 9.12,6.05, 11.35 μmol·L⁻¹, respectively.

Oligopeptides in plant medicines cited in Chinese Pharmacopoeia / 中国中药杂志

In total, 23 plant plant medicined containing oligopeptides were cited in Chinese Pharmacopoeia (1 part) of 2015 version including Rubia cordifolia, Linum usitatissimum, Aster tataricus, Psammosilene tunicoides, Pseudostellaria heterophylla, Stellaria dichotoma, Vaccaria segetalis, Dianthus superbus, Celosia argentea, Lycii Cortex, Citrus medica, C. aurantium, Panax ginseng, Parmx notoginseng, Schisandra chinensis, Sparganium stoloniferum, Euryale ferox, Ophiopogon japonicas, Pinellia ternate, Achyranthes bidentata, Physalis alkekengi, Polygonatum odoratum, and Leonuri Fructus. There were 187 oligopeptides in plant medicines above as reported. Oligopeptides consisted mainly of linear peptides and cyclic peptides. The linear peptides included dipeptides, tripeptides and pentapeptides, and cyclic peptides included cyclic, bicyclic and tricyclic peptides. The number of residues of single cyclic peptides ranged from two to twelve. Bicyclic peptides were isolated mainly from R. cordifolia and C. argentea. Modern pharmacological study showed that oligopeptides had many pharmacological effects, including antitumor, anticoagulant, antibacterial, immune suppression and so on.

Chnemical constituents from Bombyx Batryticatus / 中草药

Objective: To study the chemical constituents of Bombyx batryticatus. Methods: The chemical constituents of B. batryticatus were isolated by different column chromatographic techniques, including silica gel and Sephadex LH-20 columns. The structures of these compounds were identified by a comprehensive analysis of the spectroscopic data. Results: Eleven compounds were isolated from the EtOAc extract of B. batryticatus. The compounds were identified as cyclo (D)-Pro-(D)-Val (1), cyclo (S)-Pro-(R)-Leu (2), cyclo (D)-Pro-(D)-Ile (3), cyclo (D)-Pro-(D)-Phe (4), aurantiamid (5), (+)-pinoresinol (6), isololiolide (7), butyl-2-pyrrolidone-5-carboxylate (8), (-)-medioresinol (9), (-)-lariciresinol (10), and methylphydroxybenzeneacetate (11). Conclusion: All the compounds are isolated from B. batryticatus for the first time.

Nitrogenous chemical constituents of Weiceng / 军事医学

Objective To investigate the nitrogenous chemical constituents of Weiceng .Methods Weiceng extract was subjected to various column chromatography and spectroscopic methods were used for the elucidation of compounds .Results Seventeen compounds were isolated and identified as cyclo-(Leu-Tyr)(1), cyclo-(Phe-Tyr) (2), cyclo-(Pro-Gly) (3), L-Pyroglutamic acid methyl ester (4), uracil (5), thymine (6), N-acetylphenylalanine (7), tyrosine (8), phenylala-nine (9), phenylalanine methyl ester (10), N-methyl leucine (11), isoleucine (12), valine (13), leucine (14), glutamic acid (15), glycine (16) and aspartic acid (17).Conclusion All the seventeen compounds are isolated from Weiceng for the first time .Before this study , cyclopeptides 1-3 have never been isolated from soy bean or its products .