Turkish Journal of Chemistry, Vol.28, No.2, 227-234, 2004
Iridoid and phenylethanoid glycosides from Verbascum lasianthum
Three iridoid glucosides, 8-O-acethylharpagide (1), harpagoside (2), and 6-O-vanilloylajugol (3), were isolated from the roots of Verbascum lasianthum Boiss. ex Bentham. In addition, 2 phenylethanoid glycosides, verbascoside {=acteoside, [beta(3,4-dihydroxyphenyl)-ethyl]-(3'-O-alpha-L-rhamriopyranosyl)-(4'-O-caffeoyl)-beta-D-glucopyranoside} (4) and poliumoside {= [beta-(3,4-dihydroxyphenyl)-ethyl]-(3',6'-O-alpha-L-dirhamriopyranosyl)-(4'-O-caffeoyl)-beta-D-glucopyranoside} (5), were also isolated. The structures of all compounds were established by spectroscopic evidence (UV, TR, ID and 2D NMR, LC-ESIMS). Compounds 2-5 demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical in TLC autographic assays.
Keywords:Verbascum lasianthum;Scrophulariaceae;iridoid glucosides;8-O-acethylharpagide;harpagoside;6-O-vanilloylajugol;phenylethanoid glycosides;verbascoside (= acteoside);poliumoside;radical scavenging activity