Phenolic compounds from the aerial parts of in Japan, and their antioxidant activity and chemical adaptation to alpine environment.

Twelve flavonoids (-) including a new flavonol glycoside, hibiscetin 3--glucopyranoside-8--glucuronopyranoside, ten known galloylglucoses (-) and three known phenolic acids (-) were isolated from the aerial parts of growing in Japan. Their chemical structures were elucidated by UV-vis spectra, LC-MS, HR-MS, acid hydrolysis, NMR, and/or HPLC, and TLC comparisons with authentic samples. Antioxidant activity of major 14 compounds was measured by H-ORAC method, and two flavonols, herbacetin 3--glucoside-8--glucuronide, and gossypetin 3--glucuronide-8--glucoside, showed the strongest activity. Moreover, chemical adaptation to severe alpine environment of was discussed.