β-Orcinol-type depsides from the lichen Thamnolia vermicularis.

A phytochemical investigation of a herb tea made from Thamnolia vermicularis led to the isolation of three new β-orcinol-type depsides (1, 2 and 3), along with seven known compounds hypothamnolic acid (4), 3'-methylevenic acid (5), baeomycesic acid (6), squamatic acid (7), methyl 3'-methyllecanorate (8), barbatinic acid (9) and atranorin (10). The structures of the new compounds were determined on the basis of spectroscopic evidence, including 1-D and 2-D NMR and ESI-MS techniques.