Synthesis and biological evaluation of novel 5-alkyl-2-arylthio-6-((3,4-dihydroquinolin-1(2H)-yl)methyl)pyrimidin-4(3H)-ones as potent non-nucleoside HIV-1 reverse transcriptase inhibitors

A series of novel S-DABO analogues of 5-alkyl-2-arylthio-6-((3,4-dihydroquinolin-1(2H)-yl)methyl)pyrimidin-4(3H)-ones were synthesized and evaluated as inhibitors of human immunodeficiency virus type-1 (HIV-1). Among them, the most potent HIV-1 inhibitors were compounds 6c1,6c6, and 6b1 (EC(50)=0.24 ± 0.05, 0.38 ± 0.13, 0.39 ± 0.05 μM, respectively), which possess improved or similar HIV-1 inhibitory activity compared with nevirapine (NVP) (EC(50)=0.21 μM) and delavirdine (DLV) (EC(50)=0.32 μM). None of these compounds were active against HIV-2 replication. Furthermore, enzyme inhibitory assays were performed with selected derivatives against HIV-1 wtRT, confirming that the main target of these compounds is the HIV-1 RT and these new S-DABOs are acting as NNRTIs. The preliminary structure-activity relationship (SAR) of these new congeners is discussed briefly and rationalized by docking studies.     

Arylazolyl(azinyl)thioacetanilides. Part 10: Design, synthesis and biological evaluation of novel substituted imidazopyridinylthioacetanilides as potent HIV-1 inhibitors

In continuation of our efforts toward the discovery of potent HIV-1 NNRTIs with novel structures, we have employed a scaffold hopping strategy to explore the chemically diversed space of bioactive compounds. The original arylazolylthioacetanilide platform was replaced with different imidazopyridinyl- thioacetanilide scaffolds to yield the optimal pharmacophore moieties in order to generate novel NNRTIs with desirable potency. Some of the new compounds proved able to inhibit HIV-1 replication in the low micromolar range. In particular, compound 5b16 displayed the most potent anti-HIV-1 activity (EC(50)=0.21±0.06μM), inhibiting HIV-1 IIIB replication in MT-4 cells more effectively than dideoxycytidine (EC(50)=1.4±0.1μM) and similarly with nevirapine (EC(50)=0.20±0.10μM). Preliminary structure-activity relationship (SAR) of the newly synthesized congeners is discussed, and molecular modeling study is performed to rationalize the SAR conclusions.     

4,1-Benzoxazepinone analogues of efavirenz (Sustiva) as HIV-1 reverse transcriptase inhibitors

A series of 4,1-benzoxazepinone analogues of efavirenz (Sustiva) as potent NNRTIs has been discovered. The cis-3-alkylbenzoxazepinones are more potent then the trans isomers and can be synthesized preferentially by a novel stereoselective cyclization. The best compounds are potent orally bioavailable inhibitors of both wild-type HIV-1 and its clinically relevant K103N mutant virus, but are highly protein-bound in human plasma.     

Design and synthesis of N1-aryl-benzimidazoles 2-substituted as novel HIV-1 non-nucleoside reverse transcriptase inhibitors

A series of novel N₁-aryl-2-arylthioacetamido-benzimidazoles were synthesized and evaluated as inhibitors of human immunodeficiency virus type-1 (HIV-1). Some of them proved to be effective in inhibiting HIV-1 replication at submicromolar and nanomolar concentration acting as HIV-1 non-nucleoside RT inhibitors (NNRTIs), with low cytotoxicity. The preliminary structure–activity relationship (SAR) of these new derivatives was discussed and rationalized by docking studies.