Turkish Journal of Chemistry, Vol.28, No.6, 751-759, 2004
Acylated flavone glycosides from Veronica pectinata var. glandulosa and V-persica
This study deals with the isolation of a new acylated 5.6,7,3',4'-pentahydroxy-flavone glycoside (1) and 3 known allose-containing acylated flavone glycosides (2-4) as well as a known flavone aglycone (5) from the aerial parts of Veronica pectinata var. glandulosa. and V. persica.. The structures of the isolated compounds were determined to be 3'-hydroxy-3,-4'-O-methylscutellarein-7-O-[2"-O-alpha-L-rhamnopyranosyl-3"-O-(6''''-O-acetyl-beta-D-glucopyranosyl)]-beta-D-glucopyranoside, named sarachaside (1), 4'-O-methylisoscutellarein-7-O-2"-O-(6"'-O-acetyl-beta-D-allopyranosyl)-beta-D-glucopyranoside (2), isoscutellarein-7-O-2"-O-(6"'-O-acetyl-beta-D-allopyranosyl)-beta-D-glucopyranoside (3), 3-kydroxy4'-O-methylisoscutellarein-7-O-2"-O-(6"'-O-acetyl-beta-D-allopyranosyl)-beta-D-glucopranoside (4) and 5,4'-dihydroxy,6,7,3'-trimethoxyflavone, named circilineol (5) by extensive I-D and 2D-NMR spectroscopy. Sarachoside (1) exhibited potent radical scavenging activity against 2,2-diphenyl-1-picryhydrazyl (DPPH) radical.
Keywords:Veronica species;Scrophulariaceae;acylated flavone glycossides;sarachoside;free radical scavenging activity;DPPH