1-(5-O-Phosphono-beta-D-ribofuranosyl)-1H-1,2,4-triazole-3-carboxamide 1beta-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide-5'-phosphate 40925-28-8 ICN 3847 NSC 274937 Ribavirin-5'-phosphate Virazole 5'-phosphate