In vitro anti-human immunodeficiency virus activities of Z- and E-methylenecyclopropane nucleoside analogues and their phosphoro-L-alaninate diesters

Nucleoside analogues with a Z- or an E-methylenecyclopropane moiety were sy nthesized and examined for activity against human immunodeficiency virus ty pe 1 (HIV-1) in vitro. The addition of a methyl phenyl phosphoro-L-alaninat e moiety to modestly active analogues resulted in potentiation of their ant i-HIV-1 activity. Two such compounds, designated QYL-685 (with 2,6-diaminop urine) and QYL-609 (with adenine), were most potent against HIV-1 in vitro, with 50% inhibitory concentrations of 0.034 and 0.0026 mu M, respectively, in MT-2 cell-based assays. Both compounds were active against zidovudine-r esistant, didanosine-resistant, and multi-dideoxynucleoside-resistant infec tious clones in vitro. Further development of these analogues as potential therapies for HIV-1 infection is warranted.