Chemical constituents from flower buds of Lonicera japonica / 中草药

ABSTRACT

Objective To investigate the chemical constituents of the flower buds of Lonicera japonica. Methods The chemical constituents were isolated by repeated silica gel chromatography, Sephadex LH-20, medium pressure column chromatography and preparative HPLC, and their structures were elucidated by spectroscopic analyses and comparison of MS, 1H-NMR and 13C-NMR data with those reported in literature. Results Twelve compounds from the EtOAc fraction of L. japonica included p-hydroxybenzoic acid (1), vanillic acid (2), quercetin-3-O-α-L-rhamnopyranoside (3), kaemnpferol-3-O-β-D-glucopyranoside (4), 3',4',7-trihydroxy- 3,5-dimethoxyflavone (5), isorhamnetin (6), hyperoside (7), quercetin-7-O-β-D-glucopyranoside (8), secologanic acid (9), vogeloside (10), 5-O-caffeoylquinic acidmethylester (11) and stigmasterol (12). Conclusion Compound 5 is obtained from the plant in Lonicera Linn. for the first time; Compounds 1-4, 6, 11 and 12 are obtained from this plants for the first time.