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The present study was the first time to investigate the effects of celastrol, derived from Trypterygium wilfordii Hook F. ("Thunder of God Vine"), a traditional Chinese medicine plant, on the metabolism of model probe substrates of CYP isoforms, CYP1A2, CYP2C11, CYP2D6, CYP2E1 and CYP3A2, which are important in the metabolism of a variety of xenobiotics. The effects of celastrol on CYP1A2 (phenacetin O-deethylase), CYP2C11 (tolbutamide 4-hydroxylase), CYP2D6 (dextromethorphan O-demethylation), CYP2E1 (chlorzoxazone 6-hydroxylase) and CYP3A2 (testosterone 6β-hydroxylase) activities were investigated using rat liver microsomes. HPLC-DAD was used to measure the model substrates and metabolites. Inhibition of rat CYP isoforms (IC50) by celastrol in potency order was CYP2C11 (10.2 μM)>CYP3A2 (23.2 μM)>CYP1A2 (52.8 μM)>CYP2E1 (74.2 μM)>CYP2D6 (76.4 μM). Enzyme kinetic studies showed that the celastrol was not only a competitive inhibitor of CYP1A2 and 2C11, but also a mixed-type inhibitor of CYP3A2, with Ki of 39.2 μM, 7.05 μM and 14.2 μM, respectively. The data indicate that celastrol inhibited the metabolism of CYP1A2, 2C and 3A substrates in rat liver in vitro with a different mode of inhibition. These in vitro studies of celastrol with CYP isoforms may be helpful for the development and application of celastrol as a promising anti-cancer agent. Further systematic studies in humans in vitro and in vivo are needed to identify the interactions of celastrol with cytochrome P450s., (© 2013.)

A new coumestan, named glycyrurol, and nine phenolic compounds were isolated from the ethyl acetate extract of the roots and rhizomes of Glycyrrhiza uralensis. Their structures were elucidated based on spectroscopic analysis and literature data, and anticoagulative assay found significant antithrombotic activity of compounds 4, 8 and 10., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Two new pentacyclic triterpenes and eight known pentacyclic triterpenes were isolated from the petroleum ether extract of Liquidambaris Resina. The structural elucidation of these compounds was determined by spectroscopic data interpretation. Their cytotoxic and antiplatelet aggregation activities were examined to find potent cytotoxic and antiplatelet aggregation compounds from natural resources. The results showed that 3-keto oleane triterpenes had strong cytotoxicity against MDA-MB-435S cancer cells and that 28-carboxyl oleane triterpenes possessed significant inhibition of platelet aggregation induced by ADP., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Two new cerebrosides, 1-O-(beta-d-glucopyranosyloxy)-(2S,3S,4R,8Z)-2-[(2'R)-2'-hydroxytricosanoylamino]-8-nonadecene-3,4-diol (1) and 1-O-(beta-D-glucopyranosyloxy)-(2S,3R,4E,8Z)-2-[(2'R)-2'-hydroxynonadecanoylamino]-4,13-nonadecene-3-diol (2), were isolated from the pollen of Typha angustifolia. Their structures were elucidated by chemical and spectral means. This is the first report on the occurrence of cerebroside in Typha (Typhaceae). Compounds 1 and 2 exhibited effect on the proliferation of cultured vascular smooth muscle cell (VSMCs) induced by fatal bovine serum (FBS)., (Copyright (c) 2009 Elsevier B.V. All rights reserved.)

A new cytotoxic casbane diterpene, named pekinenal, was isolated from the roots of Euphorbia pekinensis. Its structure was elucidated as 5alpha-hydroxy-1betaH,2alphaH-casba-3Z,7E,11E-triene-18-al by a combination of 1D- and 2D-NMR techniques and confirmed by X-ray crystallography. Pekinenal showed cytotoxic activity against all four human cancer cell lines tested.

Thirteen undescribed dimeric Erythrina alkaloids, named as erythrivarines A1–A13, were isolated from the barks of Erythrina variegata L. and. Their structures were determined on the basis of NMR, UV and mass spectral analyses. Dimeric Erythrina alkaloid with a C-8/8′ linkage in erythrivarine A1 was not yet reported. Representative dimers from titled plant were used to prove their occurrence as natural products by LC − MS detection. Additionally, simultaneous investigation enabled us to propose the natural property of seemingly artificial Erythrina alkaloid with acetonyl group. Thirteen undescribed dimeric Erythrina alkaloids were isolated. Dimeric Erythrina alkaloid with a C-8/8′ linkage in erythrivarine A1 is not yet reported. Representative dimers from titled plant were proved their occurrence as natural products by LC-MS detection, which enabled us to propose the natural property of seemingly artificial products with acetonyl group. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Two new α-pinene derivatives (1–2) were isolated from the aerial parts of Angelica sinensis. Their structures were determined by spectroscopic and chemical methods to be 6β,9-dihydroxy-(+)-α-pinene (1) and 9-hydroxy-(+)-α-pinene-6β-O-D-glucoside (2). In the anticoagulative assay, compounds 1 and 2 exhibited weak antithrombin activity and strong antiplatelet aggregation activity in vitro. [Copyright &y& Elsevier]