Antibacterial constituents from Pedicularis armata.

A new neolignan glycoside named armaoside (1), together with six known compounds (2-7), have been isolated from the whole plant of Pedicularis armata Maxim. The structure of 1 was elucidated as erythro-(7S,8R)-1-(4-O-beta-D-glucopyranosyl-3-methoxyphenyl)-2-[3,5-dimethoxyl-4-oxo-cinnamic aldehyde]propane-1, 3-diol by spectroscopic and chemical methods. All compounds were assayed against Bacillus subtilis, Escherichia coli, and Staphylococcus aureus.