Alkaloids from Isopyrum thalictroides L.

Three new bisbenzylisoquinoline alkaloids, isopyruthaldine, isopythaldine and isothalmidine, containing new type of bridges were isolated from roots and rhizomes of Isopyrum thalictroides. The known isoquinoline alkaloids, reticuline, isocorydine. columbamine and palmatine, obtained from the aerial parts, are new for the genus Isopyrum. All structures were elucidated by spectroscopic analysis.