A new iridoid glycoside from Scrophularia ningpoensis

A new iridoid glycoside, named 6'-O-cinnamoylharpagide (1), has been isolated from the roots of Scrophularia ningpoensis (Scrophulariaceae) together with nine known compounds, harpagide (2), harpagoside (3), 8-O-feruloylharpagide (4), 8-O-(p-coumaroyl)harpagide (5), 6-O-methylcatalpol (6), aucubin (7), buergerinin B (8), teuhircoside (9) and 6-O-cinnamoyl-D-glucopyranose (10). Compound 10 was obtained as an inseparable mixture of 6-O-cinnamoyl-alpha-D-glucopyranose and 6-O-cinnamoyl-beta-D-glucopyranose at a ratio of 1 : 1, which is presumably formed by cleavage of compound 1. Their structures were elucidated on the basis of chemical and spectral analysis.