title: Antioxidant and cytotoxic flavonols from Calotropis procera.
abstract: Phytochemical investigations of Calotropis procera leaves have led to the isolation of two new compounds: quercetagetin-6-methyl ether 3-O-beta-D-4C1-galacturonopyranoside (3) and (E)-3-(4-methoxyphenyl-2-O-beta-D-4C1 -glucopyranoside)-methyl propenoate (4), along with eleven known metabolites: nine flavonol and two cinnamic acid derivatives. All metabolites were isolated for the first time from the genus Calotropis, except for 1 isolated previously from Calotropis gigantea. The structures were determined by spectroscopic methods (UV, ESI-MS, 1H, 13C NMR, 1H-1H COSY, HSQC, and HMBC). The radical scavenging activity of the aqueous methanol extract and compounds 8-13 was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Cytotoxic screening of the same compounds was carried out on brine shrimps as well.
authors.affiliation: Medicinal Chemistry Department, Theodor Bilharz Research Institute (TBRI), P. O. B. 12411, Giza, Egypt. tbi20042003@yahoo.co.uk
authors.forename: Mona A
authors.initials: MA
authors.lastname: Mohamed
authors.forename: Manal M
authors.initials: MM
authors.lastname: Hamed
authors.forename: Wafaa S
authors.initials: WS
authors.lastname: Ahmed
authors.forename: Allia M
authors.initials: AM
authors.lastname: Abdou
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification*; D031107:Calotropis / Q000737:chemistry*; D044948:Flavonols / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000975:Antioxidants; D044948:Flavonols