Synthesis of the 5-phosphono-pent-2-en-1-yl nucleosides: a new class of antiviral acyclic nucleoside phosphonates

A new class of acyclic nucleoside phosphonates, the 5-phosphono-pent-2-en-1-yl nucleosides and their hexadecyloxypropyl esters, were synthesized from butyn-1-ol. Only the hexadecyloxypropyl esters showed antiviral activity against herpes simplex virus type 1, in vitro. Hexadecyloxypropyl 1-(5-phosphono-pent-2-en-1-yl)-thymine was the most active and selective compound among the synthesized nucleotides with an EC50 value of 0.90 microM.