isolappaol c/lappa

From seeds of Arctium lappa L. (Asteraceae) we obtained arctigenin (1), arctiin (2), chlorogenic acid (3), 4,5-dicaffeoylquinic acid (4), 3,5-dicaffeoylquinic acid (5), 3,4-dicaffeoylquinic acid (6), matairesinol (11), isolappaol A (12), lappaol F (14), and lappaol B (15), together with 1:1 mixtures

A new butyrolactone sesquilignan, isolappaol C (1), together with four known lignans, lappaol C (2), lappaol D (3), lappaol F (4), and diarctigenin (5), were isolated from the methanolic extract of the seeds from the Arctium lappa plant. The structure of isolappaol C (1) was determined by spectral