[Chemical constituents of Eupatorii Lindleyani Herba and their lung-protective effects].

This study aimed to investigate the chemical constituents of Eupatorii Lindleyani Herba and to identify the compounds with protective effects on the lung. The petroleum ether extract of Eupatorii Lindleyani Herba was separated and purified through silica gel column chromatography, ODS column chromatography, and HPLC. The structures of the isolated compounds were identified based on their physicochemical properties and spectroscopic data. Nine compounds were obtained and identified as eupaphenolide A(1), eupaphenolide B(2), aurantiamide acetate(3), aurantiamide(4), 8β-tigloiloxi-grazielia(5),(3S,6R,7R,8R)-3-hydroxy-8-acetoxysarracenyloxy germacra-1(10),4,11(13)-trien-6,12-ilide(6), eucannabinolide(7), eupalinolide G(8), and eupachinsin A(9). Compounds 1 and 2 were newly identified. The lung-protective activities of these compounds were evaluated in vitro via the MTT assay. Germacranolide-type sesquiterpenes(5-9) showed notable protective effects, among which compound 8 at 1 μmol·L~(-1) significantly increased cell viability, exhibiting stronger activity than the positive control licochalcone A. Compounds 6, 7, and 9 at low concentrations partially reduced NNK-induced cell injury and displayed a biphasic effect characterized by protection at low concentrations and inhibition at high concentrations. These results suggest that the germacranolide-type sesquiterpenes in Eupatorii Lindleyani Herba may serve as the main active constituents responsible for its lung-protective effects, providing experimental evidence for further pharmacological research on this plant.