Assembling a smallpox biodefense by interrogating 5-substituted pyrimidine nucleoside chemical space

The nucleoside 5-formyl-2′-deoxyuridine has been used as a starting point for the generation of novel 5-substituted pyrimidine nucleosides that are shown to possess significant antiviral activity against two representative orthopoxviruses, namely vaccinia virus and cowpox virus.