Alkaloids of Thalictrum XXVII. New hypotensive aporphine-benzylisoquinoline derived dimeric alkaloids from Thalictrum minus race B.

The roots of T. minus race B have yielded, in addition to adiantifoline (1) previously isolated from this source, two new related alkaloids, thaliadine (2) and thaliadanine (5). Both were assigned complete structures by spectral methods and by chemical interconversion to adiantifoline or its product. O-Desmethyladiantifoline should have structure 14, rather than the previously reported 5. All three isolated alkaloids show hypotensive activity in rabbits, and thaliadanine (5) has antimicrobial activity against Mycobacterium smegmatis.