(Hetero)aroyl esters of 2-(N-phthalimido)ethanol and analogues: parallel synthesis, anti-HIV-1 activity and cytotoxicity

The structural simplification of the non-nucleoside reverse transcriptase inhibitors (NNRTIs) O-(2-phthalimidoethyl)-N-(hetero)aroyl-N-arylthiocarbamates led us to design (hetero)aroyl esters of 2-(N-phthalimido)ethanol as a potential new class of anti-HIV-1 agents. The setup of a solution-phase parallel synthesis method allowed the rapid preparation of a high number of analogues. In cell-based assays, 20 of 34 esters showed anti-HIV-1 activity ranging from nanomolar to micromolar concentrations. The most potent esters had only a minor effect or were ineffective in enzyme assay against HIV-1 reverse transcriptase. Variations on the O-(2-phthalimidoethyl) moiety led to compounds devoid of antiretroviral activity, but cytotoxic, in particular those bearing the 4-chloro-3-nitrobenzoyl moiety. The most cytotoxic compound displayed a CC 50 value of 1.6 μM.