Treatment of L-ribose (I) with MeOH in the presence of acid catalyst gave 1-O-methyl ribofuranoside (II), which was esterified with Ac2O in pyridine to afford triacetate (III). Subsequent treatment with Ac2O and AcOH produced tetraacetyl ribofuranoside (IV). Condensation of (IV) with methyl 1,2,4-triazole-3-carboxylate (V) using a catalytic amount of bis(p-nitrophenyl)phosphate at high temperature provided the desired nucleoside (VI) along with minor amounts of its triazole regioisomer (VII), which were separated by column chromatography. Displacement of the methyl ester of (VII) with methanolic ammonia, with concomitant deprotection of the acetate esters furnished the title carboxamide.

Treatment of L-ribose (I) with MeOH in the presence of acid catalyst gave 1-O-methyl ribofuranoside (II), which was esterified with Ac2O in pyridine to afford triacetate (III). Subsequent treatment with Ac2O and AcOH produced tetraacetyl ribofuranoside (IV). Condensation of (IV) with methyl 1,2,4-triazole-3-carboxylate (V) using a catalytic amount of bis(p-nitrophenyl)phosphate at high temperature provided the desired nucleoside (VI) along with minor amounts of its triazole regioisomer (VII), which were separated by column chromatography. Displacement of the methyl ester of (VII) with methanolic ammonia, with concomitant deprotection of the acetate esters furnished the title carboxamide.