Chemical Constituents of Tagetes patula and Their Neuroprotecting Action

Two novel flavonoids (1, 2) and 3 known compounds (3-5) were isolated from the flowers and whole plant of Tagetes patula L., and their structures were elucidated by means of ultra-high performance liquid chromatography with electrospray ionization, coupled to quadrupole-time-of-flight/mass spectrometry, 1H and 13C-nuclear magnetic resonance (NMR), as well as 2-dimensional-NMR (heteronuclear single quantum correlation and heteronuclear multiple bond correlation) and chemical methods. In addition, all the compounds were examined for their neuroprotective action on the injury of SH-SY5Y cells induced by glutamate, indicating that the protective effect of these compounds on glutamate-induced SH-SY5Y cell was marigold biflavone > patuletin > quercetin > kaempferol-3-O-β-d-glucoside > patuletin-3-O-α-l-arabinopyranoside. Thus, it could be concluded that flavonoids played a key role in the neuroprotective action of T. patula.