ABSTRACT
A total of 140,000 compounds were screened in a targetfree cell-based high throughput assay against HIV-1 infection, and a subset of 81 promising compounds was identified. Secondary screening of these 81 compounds revealed two putative human RNaseH2 inhibitors, RHI001 and RHI002, with IC50 value of 6.8 µM and 16 µM, respectively. RHI002 showed selective activity against human RNaseH2 while RHI001 inhibited HIV-RNaseH, E. coli RNaseH, and human RNaseH1 with IC50 value of 28.5 µM, 7.9 µM, and 31.7 µM, respectively. Kinetic analysis revealed that both inhibitors had non-competitive inhibitor-like properties. Because RNaseH2 is involved in the etiology of Aicardi-Goutier syndrome and has been suggested as an anticancer drug target, small molecule inhibitors modulating its activity would be useful for investigating the cellular function of this molecule.
Subject(s)
Anti-HIV Agents/pharmacology , Enzyme Inhibitors/pharmacology , HIV-1/drug effects , Pyrimidines/pharmacology , Ribonuclease H/antagonists & inhibitors , Thiophenes/pharmacology , Anti-HIV Agents/chemistry , Autoimmune Diseases of the Nervous System/drug therapy , Autoimmune Diseases of the Nervous System/etiology , Cell Line, Tumor , Drug Evaluation, Preclinical , Enzyme Inhibitors/chemistry , Escherichia coli Proteins/antagonists & inhibitors , HeLa Cells , High-Throughput Screening Assays , Humans , Molecular Structure , Nervous System Malformations/drug therapy , Nervous System Malformations/etiology , Pyrimidines/chemistry , Ribonuclease H/genetics , Ribonuclease H/metabolism , Ribonuclease H, Human Immunodeficiency Virus/antagonists & inhibitors , Ribonucleases , Thiophenes/chemistryABSTRACT
Following the previous SAR of a novel dihydropyrimidinone scaffold as HIV-1 replication inhibitors a detailed study directed towards optimizing the metabolic stability of the ester functional group in the dihydropyrimidinone (DHPM) scaffold is described. Replacement of the ester moiety by thiazole ring significantly improved the metabolic stability while retaining antiviral activity against HIV-1 replication. These novel and potent DHPMs with bioisosteres could serve as advanced leads for further optimization.
Subject(s)
HIV Reverse Transcriptase/antagonists & inhibitors , HIV-1/drug effects , Pyrimidinones/chemical synthesis , Reverse Transcriptase Inhibitors/chemical synthesis , Virus Replication/drug effects , Animals , Cell Line, Tumor , Drug Stability , HIV-1/physiology , Humans , Microsomes, Liver/metabolism , Models, Molecular , Nevirapine/pharmacology , Pyrimidinones/pharmacology , Rats , Reverse Transcriptase Inhibitors/pharmacology , Structure-Activity Relationship , Thiazoles/chemistryABSTRACT
We identified a novel class of aryl-substituted triazine compounds as potent non-nucleoside reverse transcriptase inhibitors (NNRTIs) during a high-throughput screening campaign that evaluated more than 200000 compounds for antihuman immunodeficiency virus (HIV) activity using a cell-based full replication assay. Herein, we disclose the optimization of the antiviral activity in a cell-based assay system leading to the discovery of compound 27, which possessed excellent potency against wild-type HIV-1 (EC50 = 0.2 nM) as well as viruses bearing Y181C and K103N resistance mutations in the reverse transcriptase gene. The X-ray crystal structure of compound 27 complexed with wild-type reverse transcriptase confirmed the mode of action of this novel class of NNRTIs. Introduction of a chloro functional group in the pyrazole moiety dramatically improved hERG and CYP inhibition profiles, yielding highly promising leads for further development.
