Activities of alkoxvalkyl esters of cidofovir (CDV), cyclic CDV, and (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine against orthopoxviruses in cell monolayers and in organotypic cultures

The potencies of several alkoxyalkyl esters of acyclic nucleoside phosphonates against vaccinia virus and cowpox virus were evaluated in cell monollayers and three-dimensional epithelial raft cultures. Prodrugs were at least 20-fold more active than their parent compounds. Octadecycloxyethyl-(S)-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine emerged as the most potent derivative.