An-Jun Deng

Nine new steroidal glycosides from the roots of Cynanchum stauntonii

Nine new steroidal glycosides, named as stauntosides C-K (2, 5, 7-10, 13, 14, and 16), along with seven known compounds (1, 3, 4, 6, 11, 12, and 15) were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, and HRESI-MS, and qualitative chemical methods. Their significance in terms of the chemotaxonomy of C. stauntonii is discussed.

Synthesis and Structure–Activity Relationships of Quaternary Coptisine Derivatives as Potential Anti-ulcerative Colitis Agents

Thirty quaternary coptisine derivatives from a synthesized library were found to activate the in vitro transcription of x-box-binding protein 1 (XBP1). Among these, the dihydrocoptisines were demonstrated by in vitro XBP1 transcriptional activity assays and animal experiments to be much more active anti-ulcerative colitis (UC) agents than quaternary coptisines, tetrahydrocoptisines, and the positive control. Unsubstituted dihydrocoptisine exhibited more significant anti-UC efficacy than dihydrocoptisines substituted at the C-8 or C-13 position. The EC50 value of dihydrocoptisine for XBP1 transcriptional activation was 2.25 nM. Dihydrocoptisine exhibited a significant dose-effect relationship, as indicated by biomarkers in in vitro and in vivo experiments. According to this study, the starting materials reductive states and the substitution patterns of the dihydrocoptisines were determined to be the critical parameters for modulating their anti-UC efficacy, and the dihydrocoptisine skeleton was designated as the key pharmacophore. The synthesized dihydrocoptisine is a promising lead for developing anti-UC drugs.

Chemical constituents of the stems of Ephedra sinica

A new naphthalene derivative, 1-methyl-2,3-methylenedioxy-6-naphthalenecarboxylic acid methyl ester (1), and a new alkaloid, ( ± )-1-phenyl-2-imido-1-propanol (2), together with the four known compounds, ephedrine, pseudoephedrine, N-methylephedrine, and 6-methoxykynurenic acid, have been isolated from the stems of Ephedra sinica, a famous traditional Chinese herbal medicine. The structures of 1 and 2 were determined by spectroscopic methods, including 1D- and 2D-NMR experiments as well as HR-EI-MS analysis.

Two novel biphenyl dimers from the heartwood of Caesalpinia sappan

Two novel biphenyl dimers, caesappanin A (1) and B (2), were isolated from the ethanol extract of the heartwood of Caesalpinia sappan. Their structures were elucidated on the basis of spectroscopic data including IR, HRESIMS, 1D and 2D NMR. Preliminary bioassays showed that compound 1 possessed potent cytotoxic effects against 4 cell lines including HCT-8, BGC-823, A549 and A2780 with IC(50) between 1.67μM and 4.88μM.

Fingerprinting Analysis of Rhizoma Chuanxiong of Commercial Types using 1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography Method

The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the (1)H NMR spectra of the isolated pure compounds. The (1)H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the (1)H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the (1)H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong exhibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

Osteoclast-inhibiting saikosaponin derivatives from Bupleurum Chinense

Five new saikosaponins, saikosaponin w (1), 21β-hydroxysaikosaponin b2 (2), 6″-O-acetylsaikosaponin e (3), 6″-O-acetylsaikosaponin b1 (4), and 6″-O-acetylsaikosaponin b3 (5), along with twenty-two known ones (6-27), have been isolated from the roots of Bupleurum chinense. Their structures were elucidated on the basis of detailed spectroscopic analysis, including mainly 1D and 2D NMR and HRESI-MS, qualitative chemical methods, and comparison with the literatures. Osteoclast-inhibiting activity of some of the isolated compounds was evaluated in vitro, with five ones have shown significant activity by inhibitory rates ranging from 48.3% to 56.1% at the concentration of 10μM and with significant differences among groups observed.

Fingerprinting Analysis of Saposhnikovia divaricata using 1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography

The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar and polar extracts (control substance for plant drug [CSPD] A and B) from the roots of 12 specimens of Saposhnikovia divaricata (Turcz.) Schischk were achieved with Fourier Transform (FT)-NMR spectrometer and assigned by comparison to each other and to the (1)H NMR spectra of the isolated individual compounds. These fingerprints were found to be uniform in terms of the specificity for the implication of all 12 specimens being systematically of the same origin. The uniformity was further affirmed by high performance liquid chromatography (HPLC), which also revealed exactly identical specificity for the identified S. divaricata species with the (1)H NMR appearances of corresponding CSPD on the part of the composition of characteristic constituents when comparing to corresponding individual compounds. This investigation unambiguously shows that the specific signals from the chemotaxonomically significant compounds of chromones and coumarins in S. divaricata are exhibited distinctively in the composite features of both (1)H NMR fingerprints and HPLC profiles. The (1)H NMR and HPLC profiles established can successfully be used as reference for the authentication of the origin of S. divaricata species as well as for chemotaxonomic studies.

The protective effect of epicatechin on experimental ulcerative colitis in mice is mediated by increasing antioxidation and by the inhibition of NF-κB pathway

BACKGROUND Ulcerative colitis (UC) is a chronic inflammatory intestinal disease. It is necessary to find out new effective drugs for UC. In our study epicatechin extracted from grape seed by our institute for the first time could treat UC effectively. Then anti-UC mechanisms of epicatechin were elucidated in vivo and in vitro. METHODS Dextran sulfate sodium (DSS)-induced acute UC mice model was used to evaluate the activity of epicatechin and its properties against UC. Then its anti-inflammatory and antioxidant effects were evaluated as follows: the concentrations of TNF-α and IL-6 in the colon supernatants were determined by ELISA. NO and MPO were assayed by Griess method and commercial kit respectively. NF-κB were determined by NF-κB-Dependent Reporter Gene Expression Assay and Western Blotting respectively. Antioxidant factors such as SOD, MDA, GSH-Px and CAT were also measured in colon tissues and cell supernatant stimulated by LPS respectively. RESULTS In C57BL/6J mice model with DSS-induced UC, epicatechin was able to decrease the disease activity index and colon macroscopic damage index scores, reduce body weight loss, and significantly relieve colon contracture and crypt damage. TNF-α, IL-6, NO, MPO and MDA were reduced in the mice administered epicatechin, whereas antioxidant enzymes showed increased activity in epicatechin-treated mice and cell line respectively. Furthermore, inhibition effect on NF-κB activation by epicatechin were demonstrated in vivo and in vitro. CONCLUSIONS Epicatechin has inhibitory effect on DSS-induced acute UC. This effect is mainly due to its antioxidant effect and the inhibition of inflammatory molecules related to NF-κB pathway.

New synthetic method of 8-oxocoptisine starting from natural quaternary coptisine as anti-ulcerative colitis agent.

Quaternary coptisine (1), a natural bioactive quaternary protoberberine alkaloid (QPA), was treated with potassium ferricyanide in aqueous solution of 5 N sodium hydroxide leading to the acquisition of 8-oxocoptisine (2) with much higher yield than reported in the literature. This is the first report of the oxidation of a natural QPA by applying potassium ferricyanide as an oxidant. 8-Oxocoptisine showed significant anti-ulcerative colitis efficacy in vitro with EC50 value being 8.12 × 10− 8 M.

Two new flavonoids from the roots of Scutellaria baicalensis

One new flavone, 5,7-dihydroxy-8,2′,3′,6′-tetramethoxyflavone (1), and one new flavonol, 5,7,6′-trihydroxy-2′-methoxyflavonol (2), were isolated from the roots of Scutellaria baicalensis, and their structures were elucidated on the basis of extensive spectroscopic evidences, especially 1D and 2D NMR and HR-ESI-MS experiments. The structure features of these new compounds lie in the substitution at both C-2′ and C-6′ positions of B-ring by hydroxyl or methoxyl groups.