Studies on the constituents of Broussonetia species. V. Two new pyrrolidine alkaloids, broussonetines K and L, as inhibitors of glycosidase, from Broussonetia kazinoki SIEB.

Two new pyrrolidine alkaloids, broussonetines K and L, were isolated from t he branches of Broussonetia kazinoki SIEB. (Moraceae). Broussonetines K and L were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R)-1 -hydroxy-10-oxo-13-(beta-D-glucopyranosyloxy) tridecyl] pyrrolidine (1) and (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(1R)-1-hydroxy-9-oxo-13-(be ta-D-glucopyranosyloxy) tridecyl] pyrrolidine (2), respectively, by spectro scopic and chemical methods. 1 and 2 inhibited beta-glucosidase, beta-galac tosidase and beta-mannosidase.