Lactate cannot substitute for alanine in d4T-based anti-HIV nucleotide prodrugs--despite efficient esterase-mediated hydrolysis

As part of our on-going effort to deliver masked phosphates of Antiviral nucleosides inside living cells we have previously discovered that amino acid-derived phosphoramidates are particularly effective. Here we report that lactate analogues, with a simple change of bridging nitrogen for oxygen, are virtually inactive as Antiviral agents and apparently do not achieve intracellular nucleoside phosphate delivery.