Isolation and structure elucidation of a flavone and tannic acid from sudanese sonchus oleraceus plant

Sonchus oleraceus (moleita) from the family Asteracae was investigated for its antioxidants activities. The ethyl acetate extract of the plant showed 89% radical scavenging activity (RSA). The extract was subjected to column chromatography. Solvent mixtures were used from least to highest polarities (petroleum ether till methanol). 12 fractions showed high antioxidant activity. Radical scavenging activity was tested with DPPH (1,1-Diphenyl-2-picrylhydrazyl). The structures were identified with modern spectrum techniques as 1H NMR, 13CNMR, 2D proton NMR(cosy),HSQC (heteronuclear single quantum correlation) and IR frequencies. Compound (1) is 7-hydroxy, 6 –C-glycoside, 3’ hydroxyl pyridine-flavon (0.530 gm). Solvent system for isolation was (Tol: Eth.Acet: Formic Acid). Compound (2) is tannic acid dimer (0.11 gm). Solvent system for isolation was Ethyl Acetate: Methanol (4:6).