Antioxidative Flavonol Glucuronides and Anti-HBsAg Flavonol from Rotala rotundifolia.
Two new flavonol glucuronides, quercetin 3-O-β-D-2″-acetylglucuronide (1) and quercetin 3-O-β-D-2″-acetylglucuronide methyl ester (2), along with four known flavonoids (3-6) were isolated from the whole parts of Rotala rotundifolia. The structures of 1 and 2 were elucidated by application of various spectroscopic methods, including 1D and 2D NMR techniques. Biological evaluation showed that all of isolated flavonoid compounds have potent anti-oxidative activities by DPPH and superoxide anion methods, and kaempferol (3) and quercetin (4) exhibited significant anti-HBV activity assayed by anti-HBsAg production. The HPLC fingerprint with photodiode array detection (HPLC-DAD) for quality control of R. rotundifolia partitioned EtOAc layer was also established.
National Research Institute of Chinese Medicine, Taipei 112, Taiwan.
Li-Jie
LJ
Zhang
Institute of Biochemistry and Molecular Biology, National Yang-ming University, Taipei, 112, Taiwan.
Sheau-Farn
SF
Yeh
National Research Institute of Chinese Medicine, Taipei 112, Taiwan.
Ya-Ten
YT
Yu
School of Pharmacy, Taipei Medical University, Taipei, 110, Taiwan.
Li-Ming Yang
LM
Kuo
National Research Institute of Chinese Medicine, Taipei 112, Taiwan ; The Graduate Institute of Integrated Medicine, China Medical University, Taichung, 404, Taiwan.
Yao-Haur
YH
Kuo
Anti-HBsAg; Anti-oxidative activity; Flavonol glucuronides; Rotala rotundifolia