Antioxidants and a new dihydroisocoumarins from Polygala hongkongensis Hemsl
Abstract:A new dihydroisocoumarins, 6-methoxy-8-hydroxy-3-(4-hydroxyphenyl)isochroman-1-one, named as hongkongenin (1), and seven known flavonoids were isolated from the methanol extract whole plant of Polygala hongkongensis Hemsl. Their structures were established on the basis of UV, IR, NMR, and MS spectral data. It is the first report of the occurrence of isocoumarins in Polygala, and the known compounds 2-8 were isolated from this plant for the first time. Flavonoids showed potent antioxidant activities in vitro against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, and reductive activity to Fe3+.
Document Type: Research Article
Affiliations: 1: Institute of Medicinal Plant Development, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100094, China 2: State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Shenzhen 518057, China 3: Shenyang Pharmaceutical University, Shenyang 110016, China 4: Shenyang Pharmaceutical University, Shenyang 110016, China,School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100083, China
Publication date: 2007-06-01