OBJECTIVETo study the chemical constituents of Piper longum.

METHODThe whole plant of air-dried P. longum was extracted with 95% EtOH. The EtOH extract was suspended in H2O and extracted with petroleum ether, CHCl3 and n-BuOH, successively. The compounds were isolated and purified by column chromatography from the CHCl3 fraction, and identified based on spectral analyses (MS, 1H-NMR, 13C-NMR).

RESULTEleven compounds were isolated from P. longum, and were characterized as coumaperine (1), N-5-(4-hydroxy-3-methoxyphenyl)-2E-pentenoyl piperidine (2), piperolactam A (3), 1-[1-oxo-5 (3,4-methylenedioxyphenyl) -2E,4E-pentadienyl] -pirrolidine (4), 1-[1-oxo-5 (3,4-methylenedioxyphenyl) -2E-pentenyl] -pirrolidine (5), 1-[1-oxo-9 (3,4-methylene dioxyphenyl)-2E, 8E-nonadienyl] -pyrrolidine (6), (R)-(-) -turmerone (7), octahydro-4-hydroy-3alpha-methyl-7-methylene-alpha-(1-methylethyl)-1H-indene-1-methanol (8), (+) -aphanamol I (9), bisdemethoxycurcumin (10), demethoxycurcumin (11).

CONCLUSIONCompounds 1-11 were obtained from P. longum for the first time.