2-Pyridinethiolate derivatives from branches and leaves of Polyalthia nemoralis and their cytotoxic activities / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the active constituents of the branches and leaves of Polyalthia nemoralis.</p><p><b>METHOD</b>The compounds were isolated and purified by silica gel, macroporous adsorption resin and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.</p><p><b>RESULT</b>Eight compounds were isolated and identified as zincpolyanemin (1), nickel bis-(pyridine-N-oxide-2-thiolate) (2), cupric bis (pyridine-N-oxide-2-thiolate (3), 2-methanesulfonyl-pyridine (4), 2-pyridinethiolate N-oxide (5), 2,2'-dithiodipyridine (6), 2-thiohydroxypyridin-N-oxide-2-S-beta-D-gluco pyranoside (7) and pyridine-N-oxide (8), respectively.</p><p><b>CONCLUSION</b>Compounds 2, 4-6, 8 were new natural products. The bioassays in vitro against five human tumor cell lines with MTT method showed stronger cytotoxic activities (IC50 0.05-0.09 mg x L(-1)) for compounds 1-3 and 6, and weaker cytotoxic activities (IC50 5.49-7.71 mg x L(-1)) for compound 5.</p>