Antioxidants and a new dihydroisocoumarins from Polygala hongkongensis Hemsl.
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+.
Wu
Jian-Feng
JF
Shenyang Pharmaceutical University, Shenyang 110016, China.
Chen
Si-Bao
SB
Gao
Jing-Chun
JC
Song
Hao-Liang
HL
Wu
Li-Jun
LJ
Chen
Shi-Lin
SL
Tu
Peng-Fei
PF
D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D001713:Biphenyl Compounds / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification; D006834:Hydrazines / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D020128:Inhibitory Concentration 50; D007501:Iron / Q000737:chemistry; D049934:Isocoumarins / Q000737:chemistry / Q000302:isolation & purification*; D019906:Nuclear Magnetic Resonance, Biomolecular; D009904:Optical Rotation; D010851:Picrates; D035261:Plant Components, Aerial / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D031801:Polygala / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D016166:Free Radical Scavengers; D006834:Hydrazines; D049934:Isocoumarins; D010851:Picrates; D017665:Hydroxyl Radical; C004931:1,1-diphenyl-2-picrylhydrazyl; D007501:Iron