摘要:
Four new sphingolipids: nudicaulin A [(2S, 3S, 4R, 14E)-2-{[octadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol; 1], nudicaulin B [(2S, 3S, 4R, 14E)-2-{[(2R)-2-hydroxyoctadecanoyl] amino}tetraeicos-14-ene-1,3,4-triol; 2], nudicaulin C [(2S, 3S, 4R, 14E)-2-{[(2R)-2-hydroxyoctadecanoyl]amino} tetraeicos-14-ene-1,3,4-triol-1-O-beta-D-glucopyranoside; 3], and nudicaulin D [(2S, 3S, 4R)-2-{[(2R, 3S, 12E)-2,3-dihydroxy-eicos- 12-enoyl]amino}octadecane-1,3,4-triol; 4] together with 1-hexatriacontanol, beta-sitosterol, octadecyl 4-hydroxycinnamate, elaidic acid, cholesta-5,22-diene-3,7-diol, oleanolic acid, apigenin, and beta-sitosterol 3-O-beta-D-glucopyranoside were isolated from the methanolic extract of the whole plant of Launaea nudicaulis. Their structures were elucidated using H-1 and C-13 NMR spectra and 2D NMR analyses (HMQC, HMBC, and COSY) in combination with mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) experiments and comparison with literature data of related compounds. Compounds 1-4 displayed moderate inhibitory potential against enzyme lipoxygenase in concentration-dependent manner with IC50 value ranges 103-193 mu M.