Synthesis and biological evaluation of new pyrazole- and tetrazole-related C-nucleosides with modified sugar moieties

Abstract 3(5)-Carboxamido-4-(β- d -ribofuranosyl)pyrazoles bearing 2′-benzamido ( 15 ) and 3′-mesyloxy ( 29 ) isosteric groups, as well as the tetrazole C -nucleosides with 2-benzamido-2-deoxy-β- d -ribofuranose ( 19 ) and 3-azido-3-deoxy-β- d -xylofuranose ( 36 ) as sugar segments, have been synthesized starting from d -glucose, by utilizing the 2,5-anhydro- d -glucose ethylene acetal derivatives 1 and 20 as divergent intermediates. The C -nucleosides 15 and 36 were shown to be moderate inhibitors of the in vitro growth of both N2a and BHK 21 tumour cell lines, whereas 29 showed a selective, although not potent cytotoxic activity against N2a cells. Compound 29 also showed a moderate in vitro antiviral activity towards the rabies virus.