The 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) derivativ
es have been found to be potent and specific inhibitors of human immun
odeficiency virus type 1 (HIV-1) replication in vitro. Among the compo
unds, MKC-442 (6-benzyl-1-ethoxymethyl-5-isopropyluracil) has recently
been chosen as a candidate for clinical efficacy and safety studies i
n patients with the acquired immune deficiency syndrome (AIDS).