Glycosylations of inosine and uridine nucleoside bases and synthesis of the new 1-(beta-D-glucopyranosyl)-inosine-5 ',6 ''-diphosphate

Gluco- and ribosylation of the bases of sugar protected inosine and uridine were investigated, obtaining only adducts with beta -configuration at the new glycosidic carbon; stereospecific insertion of a sugar moiety at the 1- N of inosine was achieved either using a Mitsunobu approach (for ribosylati on) or by direct coupling of 1-alpha -bromoglucose 13 with 2',3',5'-tri-O-a cetylinosine for glucosylation. 1-(beta -D-glucosyl)-inosine, chosen as sta rting substrate for glucosylated analogs of cyclic IDP-ribose, was phosphor ylated at the primary hydroxyls and tested in intramolecular pyrophosphate bond formation.