RESUMEN
Objective: To investigate the chemical constituents of the Ziziphora clinopodioides. Methods: The compounds were isolated and purified by means of various chromatographic techniques and their structures were identified on the basis of NMR spectral data. Results: Twenty-one known compounds were isolated from the ethanol extract of the dry stems of P. amarus and their structures were identified as protocatechuic acid (1), picein (2), rosmarinic acid (3), cafferic acid (4), luteolin (5), 4', 5, 7-trihydroxy isoflavone (6), irisdichotototin D (7), pinocembrin-7-O-rutinoside (8), acacetin-7-O-rutinoside (9), 4-hydroxy-3-methoxy-acetophenone-4-O-β-D-apiofuranosy-(1→6)-β-D-glucopyranoside (10), baicalein (11), kaempferide (12), chrysin-7-O-rutinoside (13), quercetin (14), apigenin (15), ploybotrin (16), 1-O-p-coumaroylglycerol (17), 5-(hydroxymethyl)-2-furancarboxaldehyde (18), acacetin (19), 6, 8-di-C-β-D-glucosylchrysin (20), and dibutyl phthalate (21). Conclusion: Compounds 5-8, 10-12, 16-18, and 20-21 are first obtained from this plant for the first time.