Two new nor-triterpene glycosides from peruvian "Uña de Gato" (Uncaria tomentosa).

Two new 27-nor-triterpene glycosides, tomentosides A (1) and B (2), were isolated from Peruvian “Una de Gato” (cat's claw, plant of origin:  Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis and chemical interconversions. This is the first report of naturally occurring pyroquinovic acid glycosides.