SYNTHESIS OF 3,7,8-TRIDEOXY-3,7-IMINO-D-THREO-L-GALACTO-OCTITOL AND ITS INHIBITION OF BETA-GLUCOSIDASES())

The readily available sopropylidene-D-glycero-D-gulo-heptono-1,4-lacto ne [(-)-5] was converted in four synthetic steps into the new iminooct itol 3,7,8-trideoxy-3,7-imino-D-threo-L-galacto-octitol [(+)-10]. Alth ough the piperidine unit of (+)-10 has the absolute configuration of b eta-D-galacto-hexopyranosides, this iminoalditol does not inhibit five commercially available beta-galactosidases. However, (+)-10 was found to be a good competitive inhibitor of beta-glucosidases from almond ( K-i = 15 mu M) and from Caldocellum saccharolyticum (K-i = 41 mu M).