Cytotoxic and genotoxic properties of artathomsonine, a new oxoberberine alkaloid from (annonaceae).

A phytochemical investigation of the liana of led to the isolation of a new oxoberberine alkaloid, 2,10-dihydroxy-3,9-dimethoxy-8-oxo-protoberberine (), along with six known compounds. Their chemical structures were elucidated by 1 D and 2 D NMR spectroscopic methods and HRESI-MS data analysis. Compounds and were selected for further investigations.

New coumarin glycosides from the leaves of Diospyros crassiflora (Hiern).

Two new 5-methylcoumarin glycosides named diosfeboside A (1) and B (2) and five known compounds namely kaempferol 3-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranoside (3), ursolic acid (4), betulinic acid (5), stigmasterol (6) and stigmasterol 3-O-β-D-glucopyranoside (7) were isolated from the leaves of Diospyros crassiflora (Hiern). Their structures were established through interpretation of 1 and 2D NMR, mass spectra analysis and comparison with reported data. In vitro cytotoxic activity of the new compounds against human carcinoma cell lines (HL-60, Bel-7402, BGC-823, and KB) was evaluated and no cytotoxicity was observed for each of them.

New friedelane triterpenoids with antimicrobial activity from the stems of Drypetes paxii.

Two new friedelane-type triterpenes named 12alpha-hydroxyfriedelane-3,15-dione and 3beta-hydroxyfriedelan-25-al, together with six known compounds were isolated from the stems of Drypetes paxii Hutch. (Euphorbiaceae). Their structures were established on the basis of conventional 1 dimensional (1D) NMR methods, 2D shift-correlated NMR experiments and mass spectra.