The synthesis of 3-O-(β-D-glucopyranosyl)- and 3-O-(β-laminaribiosyl)-isofagomines, potent inhibitors of a 1,3-β-D-glucan endo-hydrolase

The glycosylation of 4,6-O-benzylidene-N-benzyloxycarbonylisofagomine with a D-glucosyl and a laminaribiosyl trichloroacetimidate has given, after removal of protecting groups, 3-O-(beta-glucopyranosyl)- and 3-O-(beta-laminaribiosyl)-isofagomines. Also included are similar glycosylations of a related tetrahydrooxazine. 3-O-(beta-D-Glucopyranosyl)- and 3-O-(beta-laminaribiosyl)-isofagomines acted as potent inhibitors of a barley 1,3-beta-D-glucan endo-hydrolase, with ID50 values of 7.8 and 3.1 muM, respectively.