Phenylmethylphosphor-l-alaninate pronucleotides 7a, 7b, 8a, and 8b, cyclic phosphates 10a and 10b, and phosphates 11a and 11b derived from 2, 2-bis (hydroxymethyl) methylenecyclopropane analogues 1a, 1b, 2a, and 2b were synthesized and evaluated for their antiviral activity. An improved protocol for the synthesis of analogues 1a, 1b, 2a, and 2b is also described. Phosphate 11a was the most effective agent against human and murine ...