Antioxidant caffeic acid derivatives from leaves of Parthenocissus tricuspidata.
Five caffeic acid derivatives; methyl ester of caffeoylglycolic acid (1), dimethyl ester of caffeoyltartaric acid (2), dimethyl ester of caffeoyltartronic acid (3), monomethyl ester of caffeoyltartronic acid (4), methyl ester of caffeic acid (5), and some other secondary metabolites including; quercetin, quercetin 3-O-beta-D-glucuronide methyl ester, kaempferol, 3,5,7,4'-O-tetramethylkaempferol, beta-sitosterol glucoside, 2alpha-hydroxyursolic acid and 2,24-dihydroxyursolic acid, have been isolated and characterized. All the isolated compounds were characterized with the help of NMR spectroscopy and mass spectrometry. Structure of compound 3 was also confirmed by a single X-ray crystallographic technique. Isolates were evaluated for antioxidant activities and most of the tested compounds were found to be potent in DPPH free radical scavenging (IC50 = 4.56-14.17 microg/mL) and superoxide anion scavenging (IC50 = 0.58-7.39 microg/mL) assays.
Saleem
Muhammad
M
Medicinal Chemistry Research Center, Division of Life Sciences, Korea Institute of Science and Technology, PO Box 131, Cheongryang, Seoul 130-650, Korea.
Kim
Hyoung Ja
HJ
Jin
Changbae
C
Lee
Yong Sup
YS
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002109:Caffeic Acids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002417:Cattle; D016166:Free Radical Scavengers / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves; D010946:Plants, Medicinal; D013481:Superoxides / Q000378:metabolism; D027844:Vitaceae
D000975:Antioxidants; D002109:Caffeic Acids; D016166:Free Radical Scavengers; D010936:Plant Extracts; D013481:Superoxides; C040048:caffeic acid