ABSTRACT
Dengue is a global public health threat, with about half of the world's population at risk of contracting this mosquito-borne viral disease. Climate change, urbanization, and global travel accelerate the spread of dengue virus (DENV) to new areas, including southern parts of Europe and the US. Currently, no dengue-specific small-molecule antiviral for prophylaxis or treatment is available. Here, we report the discovery of JNJ-1802 as a potent, pan-serotype DENV inhibitor (EC50's ranging from 0.057 to 11 nM against the four DENV serotypes). The observed oral bioavailability of JNJ-1802 across preclinical species, its low clearance in human hepatocytes, the absence of major in vitro pharmacology safety alerts, and a dose-proportional increase in efficacy against DENV-2 infection in mice were all supportive of its selection as a development candidate against dengue. JNJ-1802 is being progressed in clinical studies for the prevention or treatment of dengue.
Subject(s)
Dengue Virus , Dengue , Hydrocarbons, Halogenated , Indoles , Mice , Humans , Animals , Serogroup , Dengue/drug therapyABSTRACT
In the absence of any approved dengue-specific treatment, the discovery and development of a novel small-molecule antiviral for the prevention or treatment of dengue are critical. We previously reported the identification of a novel series of 3-acyl-indole derivatives as potent and pan-serotype dengue virus inhibitors. We herein describe our optimization efforts toward preclinical candidates 24a and 28a with improved pan-serotype coverage (EC50's against the four DENV serotypes ranging from 0.0011 to 0.24 µM for 24a and from 0.00060 to 0.084 µM for 28a), chiral stability, and oral bioavailability in preclinical species, as well as showing a dose-proportional increase in efficacy against DENV-2 infection in vivo in mice.
Subject(s)
Dengue Virus , Dengue , Mice , Animals , Serogroup , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Dengue/drug therapy , Indoles/pharmacology , Indoles/therapeutic useABSTRACT
Dengue is the most important mosquito-transmitted viral disease and a major global health concern. Over the last decade, dengue virus (DENV) drug discovery and development has intensified, however, this has not resulted in approved DENV-specific antiviral treatments yet. DENV and hepatitis C virus (HCV) belong to the same Flaviviridae family and, in contrast to DENV, antiviral treatments for HCV have been licensed. Therefore, applying the knowledge gained on anti-HCV drugs may foster the discovery and development of dengue antiviral drugs. Here, we screened a library of compounds with established anti-HCV activity in a DENV-2 sub-genomic replicon inhibition assay and selected compounds with single-digit micromolar activity. These compounds were advanced into a hit-to-lead medicinal chemistry program resulting in lead compound JNJ-1A, which inhibited the DENV-2 sub-genomic replicon at 0.7 µM, in the absence of cytotoxicity. In addition, JNJ-1A showed equipotent antiviral activity against DENV serotypes 1, 2, and 4. In vitro resistance selection experiments with JNJ-1A induced mutation T108I in non-structural protein 4B (NS4B), pointing towards a mechanism of action linked to this protein. Collectively, we described the discovery and characterization of a novel DENV inhibitor potentially targeting NS4B.
Subject(s)
Antiviral Agents/pharmacology , Dengue Virus/drug effects , Drug Resistance, Viral/genetics , Viral Nonstructural Proteins/genetics , Virus Replication/drug effects , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacokinetics , Antiviral Agents/toxicity , Cell Line, Tumor , Chlorocebus aethiops , Dengue , Dengue Virus/genetics , Dengue Virus/physiology , Drug Discovery , Drug Resistance, Viral/drug effects , Hepacivirus/genetics , Humans , Mutation , RNA, Viral/genetics , Replicon/drug effects , Sequence Analysis, RNA , Small Molecule Libraries , Vero CellsABSTRACT
In this study, we screened a library of 500 compounds for fungicidal activity via induction of endogenous reactive oxygen species (ROS) accumulation. Structure-activity relationship studies showed that piperazine-1-carboxamidine analogues with large atoms or large side chains substituted on the phenyl group at the R(3) and R(5) positions are characterized by a high ROS accumulation capacity in Candida albicans and a high fungicidal activity. Moreover, we could link the fungicidal mode of action of the piperazine-1-carboxamidine derivatives to the accumulation of endogenous ROS.
Subject(s)
Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Candida albicans/drug effects , Piperazines/pharmacology , Reactive Oxygen Species/metabolism , Antifungal Agents/chemical synthesis , Candida albicans/metabolism , Drug Design , Piperazines/chemical synthesis , Structure-Activity RelationshipABSTRACT
The synthesis and evaluation of benzetimide derivatives showing potent CXCR3 antagonism are described. Optimization of the screening hits led to the identification of more potent CXCR3 antagonists devoid of anti-cholinergic activity and identification of the key pharmacophore moieties of the series.
Subject(s)
Dexetimide/pharmacology , Receptors, CXCR3/antagonists & inhibitors , Dexetimide/chemistry , Humans , Structure-Activity RelationshipABSTRACT
The interaction between CC chemokine receptor 2 (CCR2) with monocyte chemoattractant proteins, such as MCP-1, regulates the activation and recruitment of inflammatory leukocytes. In this study, we characterized (S)-3-[3,4-difluoro-phenyl)-propyl]-5-isoxazol-5-yl-2-thioxo-2,3-dihydro-1H-imidazole-4-carboxyl acid methyl ester (JNJ-27141491) as a noncompetitive and orally active functional antagonist of human (h)CCR2. JNJ-27141491 strongly suppressed hCCR2-mediated in vitro functions, such as MCP-1-induced guanosine 5'-O-(3-[(35)S]thio)triphosphate binding; MCP-1, -3, and -4-induced Ca(2+) mobilization; and leukocyte chemotaxis toward MCP-1 (IC(50) = 7-97 nM), whereas it had little or no effect on the function of other chemokine receptors tested. The inhibition of CCR2 function was both insurmountable and reversible, consistent with a noncompetitive mode of action. JNJ-27141491 blocked the binding of (125)I-MCP-1 to human monocytes (IC(50) = 0.4 microM), but it failed to affect MCP-1 binding to mouse, rat, and dog cells (IC(50) > 10 microM). Therefore, transgenic mice, in which the mouse (m)CCR2 gene was replaced by the human counterpart, were generated for in vivo testing. In these mice, oral administration of JNJ-27141491 dose-dependently [5-40 mg/kg q.d. (once daily) or b.i.d.] inhibited monocyte and neutrophil recruitment to the alveolar space 48 h after intratracheal mMCP-1/lipopolysaccharide instillation. Furthermore, treatment with JNJ-27141491 (20 mg/kg q.d.) significantly delayed the onset and temporarily reduced neurological signs in an experimental autoimmune encephalomyelitis model of multiple sclerosis. Taken together, these results identify JNJ-27141491 as a noncompetitive, functional antagonist of hCCR2, capable of exerting oral anti-inflammatory activity in transgenic hCCR2-expressing mice.
Subject(s)
Imidazoles/pharmacology , Receptors, CCR2/antagonists & inhibitors , Administration, Oral , Amino Acid Sequence , Animals , CHO Cells , Calcium/metabolism , Cell Movement/drug effects , Chemokine CCL2/metabolism , Chemokine CCL2/pharmacology , Cricetinae , Cricetulus , Dogs , Dose-Response Relationship, Drug , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Molecular Sequence Data , Rats , Rats, Inbred Lew , Receptors, CCR2/metabolismABSTRACT
We recently reported the discovery of a series of 2-thioimidazoles as CCR2 antagonists. The most potent molecules of this series, the 4,5-diesters, were rapidly hydrolyzed to the inactive acids and were found to be metabolically unstable. Herein we describe the synthesis of a number of analogues with heterocyclic bioisosteric replacements of the ester group(s). Small 5-membered heterocyclic substituents at the 4-position gave highly potent CCR2 antagonists. Hydrolysis of the 5-ester is diminished, thus imparting these compounds with sufficient stability and systemic exposure after oral administration to warrant further study of the in vivo pharmacology of these functional CCR2 inhibitors.
Subject(s)
Imidazoles/chemical synthesis , Receptors, CCR2/antagonists & inhibitors , Administration, Oral , Animals , Biological Availability , Calcium/metabolism , Cell Line , Chemokine CCL2/antagonists & inhibitors , Drug Stability , Humans , Imidazoles/pharmacokinetics , Imidazoles/pharmacology , Male , Rats , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
The influx of leukocytes (eosinophils, lymphocytes, and monocytes) into the airways and their production of proinflammatory cytokines contribute to the severity of allergic asthma. We describe here the synthesis and pharmacological evaluation of a series of triazinylphenylalkylthiazolecarboxylic acid esters that were designed to act as lung-specific antedrugs and inhibitors of the production of interleukin (IL)-5, a primary eosinophil-activating and proinflammatory cytokine. Closer examination of the hydroxypropyl ester, 15, indicated its high metabolic stability (t(1/2) > 240 min) in human lung S9 fraction but rapid conversion (t(1/2) = 15 min) into the pharmacologically inactive carboxylic acid by human liver preparations. In stimulated human whole blood cultures, 15 reduced not only the production of IL-5 (IC(50) = 78 nM) but also the biosynthesis of the monocyte chemotactic proteins MCP-1 (IC(50) = 220 nM), MCP-2 (IC(50) = 580 nM), and MCP-3 (IC(50) = 80 nM). In vivo, intratracheal administration of 15 (6 mg/animal) to allergic sheep, either before (-4 h) or after (+1.5 h) the pulmonary allergen challenge, completely abrogated the late-phase airway response and reduced the bronchial hyperreactivity to inhaled carbachol.
Subject(s)
Asthma/drug therapy , Bronchodilator Agents/chemical synthesis , Cytokines/antagonists & inhibitors , Thiazoles/chemical synthesis , Triazines/chemical synthesis , Adult , Animals , Asthma/immunology , Asthma/physiopathology , Bronchodilator Agents/metabolism , Bronchodilator Agents/pharmacology , Chemokine CCL2/antagonists & inhibitors , Chemokine CCL2/biosynthesis , Chemokine CCL7 , Chemokine CCL8 , Cytokines/biosynthesis , Esters/chemical synthesis , Esters/metabolism , Esters/pharmacology , Humans , In Vitro Techniques , Interleukin-4/antagonists & inhibitors , Interleukin-4/biosynthesis , Interleukin-5/antagonists & inhibitors , Interleukin-5/biosynthesis , Interleukin-8/antagonists & inhibitors , Interleukin-8/biosynthesis , Liver/metabolism , Lung/metabolism , Monocyte Chemoattractant Proteins/antagonists & inhibitors , Monocyte Chemoattractant Proteins/biosynthesis , Sheep , Thiazoles/metabolism , Thiazoles/pharmacology , Triazines/metabolism , Triazines/pharmacologyABSTRACT
We describe the synthesis and SAR of a new class of CCR2 antagonists based on 2-mercaptoimidazole scaffold. The initial lead 1a was optimized to the 3,4-disubstituted analogues 1p-(S) and 1q-(S), which have IC(50) values in the MCP-1 induced Ca-flux below 0.01 microM.