Chemical Constituents of Pedicularis densispica Franch

An ethanol extract of the dried aerial of Pedicularis densispica Franch (Scrophulariaceae) afforded a new lignan, densispicoside (1), and two new iridoids, densispicnin C and D (14, 15), together with four lignans, (+)-isolarisiresinol 3a-O-beta-D-glucopyranoside (2), (-)-pinoresinol-beta-D-glucopyranoside (3), syringaresinol mono-beta-D-glucopyranoside (4), longifloroside B (5), eight phenylpropanoids, 4-O-beta-D-glucopyranosyl-sinapic acid methyl ester (6), 3-(4-hydroxy-3-methoxyphenyl)-1,2,3-propantriol (7), citrusin C (8), robustaside B (9), verbascoside (10), martynoside (11), 2 ''-O-acetylverbascoside (12), cis-martynoside (13), and two iridoid glycosides, shanzhiside methyl ester (16), and 8-epiloganin (17). Their structures were established on the basis of chemical and spectroscopic studies. Bioactivity results indicate that P. densispica shows activity on PAI-1 antithrombus assay in vitro and antifatigue activities in vivo.