In vitro Evaluation of AraC Prodrugs for Their Antiviral Activity

The araC prodrugs (1~5) carrying a special acyl group at 5'-Ο-or $N^4$-position were evaluated for in vitro antiviral activity against various human viruses. When tested against HSV-1 and HSV-2 cultured in the verso cells, the prodrugs exhibited slightly higher $ED_{50}$ values compared with one of the parent araC but showed more increased $CC_{50}$ values in all cases. Consequently the overall selectivity indexes of prodrugs were higher than that of arab. The prodrugs, except compound 5, exhibited very potent activity similar to that of araC ($ED_{50}$ about $0.12{\mu}g/mι$) when evaluated against another human DNA virus, cytomegarovirus. However, theses araC prodrugs were completely inactive against RNA viruses i.e. poliovirus and coxackie B3 virus at the concentration of 4250{\mu}g/mι.$