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Two compounds ( 1 and 2 ) have been isolated from the stem bark of Dysoxylum binectariferum (Roxb.) Hook. f. ex Bedd. Compound 1 is rohitukine {5,7-dihydroxy-2-methyl-8-[4-(3-hydroxy-1-methyl)-piperidinyl]-4 H -1-benzopyran-4-one}, a known compound that has anti-inflammatory and immunomodulatory activities. Compound 2 is a new alkaloid, named rohitukine N -oxide, the structure of which was elucidated on the basis of spectral evidences and comparison with the 1 H NMR data of rohitukine. [ABSTRACT FROM AUTHOR]

Weisiensin B, a new ent-kaurane diterpenoid, was isolated from traditional Chinese herb Rabdosia weisiensis C.Y. Wu. In this study, cytotoxicity of weisiensin B was tested on four different tumor cell lines and the effect of growth inhibition and apoptosis in BEL-7402 cell line were investigated in vitro. The results indicated that weisiensin B had significant antiproliferation activity on the four cell lines. Further study on BEL-7402 cells involving Hoechst 33258 stain and DNA fragmentation assay revealed the characteristic apoptotic features of nuclear and DNA ladder formation. Flow cytometric (FCM) analysis with propidium iodide (PI) staining demonstrated that BEL-7402 cells treated with weisiensin B were arrested in G2/M phase. The results demonstrated that a significant fraction of weisiensin B-treated cells died by an apoptotic pathway in BEL-7402 cells. [ABSTRACT FROM AUTHOR]

Three new phenolic constituents 1–3 were obtained from the 95% ethanol extract of the roots of Phyllodium pulchellum (Leguminosae). Their structures were elucidated on the basis of spectroscopic analyses, such as NMR, UV, IR, HR-ESI-MS, and CD. Furthermore, in an in vitro bioassay, all compounds were tested for inhibitory effects against the proliferation of acetaldehyde-stimulated HSC-T6 cells, and compound 3 exhibited potent inhibitory activity with the IC50 value of 7.6 μM. [ABSTRACT FROM AUTHOR]

The microbiological transformation of the triterpene nigranoic acid (3,4-secocycloarta-4(28),24(Z)-diene-3,26-dioic acid) (1) to 3,4-secocycloarta-4(28),17(20),24(Z)-triene-7β-hydroxy-16β,26-lactone-3-oic acid (2) and 3,4-secocycloarta-4(28),17(20)(Z),24(Z)-triene-7β-hydroxy-16β-methoxy-3,26-dioic acid (3) by the freshwater fungus Dictyosporium heptasporum YMF1.01213 has been demonstrated. The structures of the biotransformation products were determined by spectroscopic and MS analyses. Compound 2, characterized by the presence of a formed C-16/C-26 ester bridge, provided a novel nine-membered lactone ring structural skeleton for 3,4-secocycloartane triterpenoid derivatives. In addition, Compounds 1–3 exhibited weak anti-HIV activity in vitro. Compounds 2 and 3 were reported for the first time as natural product derivatives. [ABSTRACT FROM AUTHOR]