Reaction of 6-chloropyrimidines with diethyl [(2-aminoethoxy)methyl]phospho
nate allows for a ready access to acyclic nucleoside phosphonates. A series
of 5-substituted pyrimidines bearing a phosphonate side chain at position
6 were synthesized and tested against herpes simplex viruses (HSV-1 and HSV
-2) and human immunodeficiency virus (HIV-1). Some compounds showed weak an
tiviral activity against HSV-1.