Constituents from Solidago virgaurea var. gigantea and their inhibitory effect on lipid accumulation

In this study, the anti-adipogenic activities of compounds isolated from Solidago viraurea var. gigantea (SG) extracts were investigated using Oil Red O staining in the 3T3-L1 cell line. Four known compounds including 3,5-di-O-caffeoylquinic acid (5), protocatechuic acid (6), chlorogenic acid (7), and kaempferol-3-O-rutinoside (8), and four undescribed compounds including (1R,2S,3S,5R,7S)-methyl 7-((cinnamoyloxy)methyl)-2,3-dihydroxy-6,8-dioxabicyclo[3.2.1]octane-5-carboxylate (1), (1R,2S,3S,5R,7S)-methyl 2,3-dihydroxy-7-((((Z)-3-phenylacryloyl)oxy)methyl)-6,8-dioxabicyclo[3.2.1]octane-5-carboxylate (2), (1R,2S,3S,5R,7S)-2,3-dihydroxy-7-((((Z)-3-phenylacryloyl)oxy)methyl)-6,8-dioxabicyclo[3.2.1]octane-5-carboxylic acid (3), and (1R,2S,3S,5R,7S)-7-((cinnamoyloxy)methyl)-2,3-dihydroxy-6,8-dioxabicyclo[3.2.1]octane-5-carboxylic acid (4) were isolated from S. viraurea var. gigantea. The structures of the compounds were first identified by comparing their ¹H NMR spectra with spectral data from the literature and a more detailed identification was then performed using 2D NMR (Correlated spectroscopy (COSY), heteronuclear single quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and nuclear overhauser spectroscopy (NOESY)), and X-ray crystallography analyses. The anti-adipogenic activities of all compounds were evaluated by MTT assay and Oil Red O staining in 3T3-L1 cells. 3,5-di-O-caffeoylquinic acid was found to inhibit lipid accumulation more potently than the other tested compounds.