Synthesis of new acyclic pyrimidine nucleoside analogs as potential antiviral drugs.

The synthesis of 6-[N-(4-hydroxybutyl)amino]pyrimidinone derivatives 18-23 and the acyclic phosphonate nucleoside analogs 29-30 is reported. Their cytotoxic and antiviral effects were investigated. 2,5-Diamino-6-[N-[2-(phosphonomethoxy)ethyl]amino]pyrimidin-4(3H)- one (30) showed strong antiviral effects, and 21 showed significant cytotoxic activity.