Synthesis of 3-β-d-ribofuranosyl-1 H-pyrazole-4-carboxamide

The synthesis of 3-β-d-ribofuranosyl-1 H-pyrazole-4-carboxamide (11) is described. Treatment of enaminone glycoside 1 with trimethyl orthoformate afforded the aldehyde 2. The aldehyde 2 was oximated with hydroxylamine. Oxime 3 was cyclized with hydrazine to afford the pyrazole 8. The pyrazole 8 was dehydrated with acetic anhydride, and the nitrile 9 was treated with nickel acetate in acetic acid. The resulting carboxamide 10 was deblocked by aq ammonia gave 11.