6,8-Di-C-methyl-flavonoids with neuroprotective activities fromRhododendron fortunei

July 28, 2017

Title

6,8-Di-C-methyl-flavonoids with neuroprotective activities fromRhododendron fortunei

Author

Yongji Lai, Hong Zeng, Meijun He, Huiqin Qian, Zhaodi Wu, Zengwei Luo, Yongbo Xue, Guangmin Yao, Yonghui Zhang

Year

2016

Journal

Fitoterapia

Abstract

Six 6,8-di-C-methyl-flavonoids, (2R,3R)-6,8-di-C-methyl-5,7,4′-trihydroxyflavanonol 7-O-β-d-gluco-pyranoside (1), (2R,3R)-6,8-di-C-methyl-5,7,4′-trihydroxyflavanonol 7-O-β-d-xylopyranosyl(1 → 6)-β-d-glucopyranoside (2), 6,8-di-C-methylkaempferol 7-O-β-d-glucopyranoside (3), (2R)-farrerol (4a), (2R/2S)-farrerol 7-O-β-d-glucopyranoside (5), and (2R/2S)-farrerol 7-O-β-d-xylopyranosyl(1 → 6)-β-d-glucopyranoside (6), and four known analogues, farrerol (4b), (2R,3R)-6,8-di-C-methyldihydrokae-mpferol (7), 6,8-di-C-methylkaempferol 7-O-β-d-glucopyranoside (8), and 6,8-di-C-methylkaempferol (9), were isolated from the twigs and leaves of Rhododendron fortunei. The structures of compounds 1–9 were determined by spectroscopic analyses (HRESIMS, 1D and 2D NMR, and CD) and chemical methods. Compounds 1–9 were evaluated for their neuroprotective effects on the human neuroblastoma SH-SY5Y cells apoptosis induced by hydrogen peroxide (H2O2) and amyloid β peptide (Aβ), respectively. Compounds 1–3and 5–9 exhibited significant neuroprotective effects against H2O2-induced SH-SY5Y cell apoptosis, and compound 8 exhibited the strongest activity with a improvement of cell viability by about 30% at the concentration of 10 μM. Compounds 1–9 showed significant neuroprotective effects against Aβ-induced SH-SY5Y cell apoptosis.

Instrument

J-810

Keywords

Circular dichroism, Absolute configuration, Medicinal, Pharmaceutical