ABSTRACT
Inhibition of the bromodomain and extra-terminal (BET) family of adaptor proteins is an attractive strategy for targeting transcriptional regulation of key oncogenes, such as c-MYC. Starting with the screening hit 1, a combination of structure-activity relationship and protein structure-guided drug design led to the discovery of a differently oriented carbazole 9 with favorable binding to the tryptophan, proline, and phenylalanine (WPF) shelf conserved in the BET family. Identification of an additional lipophilic pocket and functional group optimization to optimize pharmacokinetic (PK) properties culminated in the discovery of 18 (BMS-986158) with excellent potency in binding and functional assays. On the basis of its favorable PK profile and robust in vivo activity in a panel of hematologic and solid tumor models, BMS-986158 was selected as a candidate for clinical evaluation.
Subject(s)
Antineoplastic Agents/pharmacology , Carbazoles/pharmacology , Drug Discovery , Phenylalanine/pharmacology , Proline/pharmacology , Tryptophan/pharmacology , Administration, Oral , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/chemistry , Carbazoles/administration & dosage , Carbazoles/chemistry , Cell Cycle Proteins/antagonists & inhibitors , Cell Cycle Proteins/metabolism , Dose-Response Relationship, Drug , Humans , Molecular Structure , Phenylalanine/administration & dosage , Phenylalanine/chemistry , Proline/administration & dosage , Proline/chemistry , Structure-Activity Relationship , Transcription Factors/antagonists & inhibitors , Transcription Factors/metabolism , Tryptophan/administration & dosage , Tryptophan/chemistryABSTRACT
A series of aminothiazoles that are potent inhibitors of LIM kinases 1 and 2 is described. Appropriate choice of substituents led to molecules with good selectivity for either enzyme. An advanced member of the series was shown to effectively interfere with the phosphorylation of the LIM kinases substrate cofilin. Consistent with the important role of the LIM kinases in regulating cytoskeletal structure, treated cells displayed dramatically reduced F-actin content.
Subject(s)
Actin Depolymerizing Factors/metabolism , Lim Kinases/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Thiazoles/pharmacology , Cell Line , Crystallography, X-Ray , Dose-Response Relationship, Drug , Humans , Lim Kinases/metabolism , Models, Molecular , Molecular Structure , Phosphorylation/drug effects , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Structure-Activity Relationship , Thiazoles/chemical synthesis , Thiazoles/chemistryABSTRACT
Previously disclosed dihydropyrazolopyrimidines are potent and selective blockers of I(Kur) current. A potential liability with this chemotype is the formation of a reactive metabolite which demonstrated covalent binding to protein in vitro. When substituted at the 2 or 3 position, this template yielded potent I(Kur) inhibitors, with selectivity over hERG which did not form reactive metabolites. Subsequent optimization for potency and PK properties lead to the discovery of ((S)-5-(methoxymethyl)-7-(1-methyl-1H-indol-2-yl)-2-(trifluoromethyl)-4,7-dihydropyrazolo[1,5-a]pyrimidin-6-yl)((S)-2-(3-methylisoxazol-5-yl)pyrrolidin-1-yl)methanone (13j), with an acceptable PK profile in preclinical species and potent efficacy in the preclinical rabbit atrial effective refractory period (AERP) model.
Subject(s)
Kv1.5 Potassium Channel/antagonists & inhibitors , Pyrazoles/chemical synthesis , Pyrimidines/chemical synthesis , Animals , Dogs , Heart/drug effects , Heart/physiology , Humans , Pyrazoles/pharmacokinetics , Pyrazoles/pharmacology , Pyrimidines/pharmacokinetics , Pyrimidines/pharmacology , Rabbits , Rats , Refractory Period, Electrophysiological/drug effects , Stereoisomerism , Structure-Activity RelationshipABSTRACT
A kinome-wide selectivity screen of >20000 compounds with a rich representation of many structural classes has been completed. Analysis of the selectivity patterns for each class shows that a broad spectrum of structural scaffolds can achieve specificity for many kinase families. Kinase selectivity and potency are inversely correlated, a trend that is also found in a large set of kinase functional data. Although selective and nonselective compounds are mostly similar in their physicochemical characteristics, we identify specific features that are present more frequently in compounds that bind to many kinases. Our results support a scaffold-oriented approach for building compound collections to screen kinase targets.
Subject(s)
Phosphotransferases/antagonists & inhibitors , Phosphotransferases/chemistry , Protein Kinase Inhibitors/chemistry , Quantitative Structure-Activity Relationship , Small Molecule Libraries , Cyclin-Dependent Kinase 2/antagonists & inhibitors , Cyclin-Dependent Kinase 2/chemistry , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/chemistry , High-Throughput Screening Assays , Protein Binding , Sequence Homology, Amino Acid , fms-Like Tyrosine Kinase 3/antagonists & inhibitors , fms-Like Tyrosine Kinase 3/chemistryABSTRACT
A series of 2,2-dimethyl-3,3-diphenyl-propanamides as novel glucocorticoid receptor modulators is reported. SAR exploration led to the identification of 4-hydroxyphenyl propanamide derivatives displaying good agonist activity in GR-mediated transrepression assays and reduced agonist activity in GR-mediated transactivation assays. Compounds 17 and 30 showed anti-inflammatory activity comparable to prednisolone in the rat carrageenan-induced paw edema model, with markedly decreased side effects with regard to increases in blood glucose and expression of hepatic tyrosine aminotransferase. A hypothetical binding mode accounting for the induction of the functional activity by a 4-hydroxyl group is proposed.
Subject(s)
Amides/pharmacology , Receptors, Glucocorticoid/agonists , Amides/chemistry , Animals , Models, Molecular , RatsABSTRACT
Leukocyte function-associated antigen-1 (LFA-1), also known as CD11a/CD18 or alpha(L)beta(2), belongs to the beta(2) integrin subfamily and is constitutively expressed on all leukocytes. The major ligands of LFA-1 include three intercellular adhesion molecules 1, 2, and 3 (ICAM 1, 2, and 3). The interactions between LFA-1 and the ICAMs are critical for cell adhesion, and preclinical animal studies and clinical data from the humanized anti-LFA-1 antibody efalizumab have provided proof-of-concept for LFA-1 as an immunological target. This article will detail the structure-activity relationships (SAR) leading to a novel second generation series of highly potent spirocyclic hydantoin antagonists of LFA-1. With significantly enhanced in vitro and ex vivo potency relative to our first clinical compound (1), as well as demonstrated in vivo activity and an acceptable pharmacokinetic and safety profile, 6-((5S,9R)-9-(4-cyanophenyl)-3-(3,5-dichlorophenyl)-1-methyl-2,4-dioxo-1,3,7-triazaspiro-[4.4]nonan-7-yl)nicotinic acid (2e) was selected to advance into clinical trials.
Subject(s)
Hydantoins/pharmacokinetics , Immunologic Factors/chemistry , Lymphocyte Function-Associated Antigen-1/drug effects , Nicotinic Acids/pharmacokinetics , Humans , Hydantoins/pharmacology , Lymphocyte Function-Associated Antigen-1/chemistry , Lymphocyte Function-Associated Antigen-1/immunology , Nicotinic Acids/toxicity , Structure-Activity RelationshipABSTRACT
Dihydropyrazolopyrimidines with a C6 heterocycle substituent were found to have high potency for block of K(V)1.5. Investigation of the substitution in the benzimidazole ring and the substituent in the 5-position of the dihydropyrazolopyrimidine ring produced 31a with an IC50 for K(V)1.5 block of 0.030muM without significant block of other cardiac ion channels. This compound also showed good bioavailability in rats and robust pharmacodynamic effects in a rabbit model.
Subject(s)
Kv1.5 Potassium Channel/antagonists & inhibitors , Potassium Channel Blockers/pharmacology , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Animals , Atrial Fibrillation/drug therapy , Cell Line , Humans , Kv1.5 Potassium Channel/metabolism , Mice , Potassium Channel Blockers/chemistry , Potassium Channel Blockers/pharmacokinetics , Pyrazoles/chemistry , Pyrazoles/pharmacokinetics , Pyrimidines/chemistry , Pyrimidines/pharmacokinetics , Rabbits , Rats , Structure-Activity RelationshipABSTRACT
Hit to Lead optimization and SAR development led to the identification of the potent and selective benzo[d]imidazole inhibitor (17b) of Co-activator Associated Arginine Methyltransferase (CARM1).
Subject(s)
Antineoplastic Agents/chemistry , Benzimidazoles/chemistry , Enzyme Inhibitors/chemistry , Piperidines/chemistry , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Drug Design , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Piperidines/chemical synthesis , Piperidines/pharmacology , Protein-Arginine N-Methyltransferases/metabolism , Structure-Activity RelationshipABSTRACT
Eg5 is a kinesin whose inhibition leads to cycle arrest during mitosis, making it a potential therapeutic target in cancers. Circular dichroism and isothermal titration calorimetry of our pyrrolotriazine-4-one series of inhibitors with Eg5 motor domain revealed enhanced binding in the presence of adenosine 5'-diphosphate (ADP). Using this information, we studied the interaction of this series with ADP-Eg5 complexes using a thermal shift assay. We measured up to a 7 degrees C increase in the thermal melting (T(m)) of Eg5 for an inhibitor that produced IC(50) values of 60 and 130 nM in microtubule-dependent adenosine triphosphatase (ATPase) and cell-based cytotoxicity assays, respectively. In general, the inhibitor potency of the pyrrolotriazine-4-one series in in vitro biological assays correlated with the magnitude of the thermal stability enhancement of ADP-Eg5. The thermal shift assay also confirmed direct binding of Eg5 inhibitors identified in a high-throughput screen and demonstrated that the thermal shift assay is applicable to a range of chemotypes and can be useful in evaluating both potent (nM) and relatively weakly binding (microM) leads. Overall, the thermal shift assay was found to be an excellent biophysical method for evaluating direct binding of a large number of compounds to Eg5, and it complemented the catalytic assay screens by providing an alternative determination of inhibitor potency.
Subject(s)
Biochemistry/methods , Kinesins/chemistry , Pyrroles/analysis , Pyrroles/chemistry , Triazines/analysis , Triazines/chemistry , Adenosine Diphosphate/metabolism , Biophysical Phenomena , Calorimetry , Cell Line, Tumor , Circular Dichroism , Humans , Kinesins/metabolism , Magnetic Resonance Spectroscopy , Models, Molecular , Protein Binding , Protein Denaturation , Protein Folding , Protein Structure, Tertiary , TemperatureABSTRACT
Design, synthesis, and SAR development led to the identification of the potent, novel, and selective pyrazole based inhibitor (7f) of Coactivator Associated Arginine Methyltransferase (CARM1).
Subject(s)
Enzyme Inhibitors/chemistry , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Pyrazoles/chemistry , Drug Design , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Humans , Protein-Arginine N-Methyltransferases/metabolism , Pyrazoles/chemical synthesis , Pyrazoles/pharmacology , Structure-Activity RelationshipABSTRACT
A series of dihydro-9,10-ethano-anthracene-11-carboxamides as novel glucocorticoid receptor modulators is reported. SAR exploration identified compounds from this series displaying a promising dissociation profile in discriminating between transrepression and transactivation activities. 17a is a partial agonist of GR-mediated transactivation which elicits potent and efficacious transrepression in reporter gene assays. A hypothetical binding mode is provided which accounts for the induction of functional activity by a bridgehead methyl group.
Subject(s)
Anthracenes/pharmacology , Drug Discovery , Receptors, Glucocorticoid/metabolism , Anthracenes/chemistry , Cell Line , Crystallography, X-Ray , Drug Discovery/methods , Glucocorticoids/chemistry , Glucocorticoids/pharmacology , Humans , Protein Binding/drug effects , Protein Binding/physiology , Receptors, Glucocorticoid/agonists , Receptors, Glucocorticoid/physiology , Structure-Activity RelationshipABSTRACT
A series of dihydropyrazolopyrimidine inhibitors of K(V)1.5 (I(Kur)) have been identified. The synthesis, structure-activity relationships and selectivity against several other ion channels are described.
Subject(s)
Chemistry, Pharmaceutical/methods , Potassium Channel Blockers/chemical synthesis , Potassium Channels, Voltage-Gated/antagonists & inhibitors , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Animals , Atrial Fibrillation/metabolism , Cell Line , Drug Design , Humans , Ions/chemistry , Mice , Models, Chemical , Potassium Channel Blockers/pharmacology , Stereoisomerism , Structure-Activity RelationshipABSTRACT
Fragment-like inhibitors of mitogen-activated protein kinase-activated protein kinase 2 (MK2) include 5-hydroxyisoquinoline (IC50 approximately 85 microM). Modeling studies identified four possible binding modes for this compound. Two-dimensional (1)H-(1)H NOESY data obtained with selectively protonated samples of MK2 in complex with 5-hydroxyisoquinoline demonstrated that two of the four predicted binding modes are well populated. A second small isoquinoline was subsequently shown to bind in a single mode. NMR and modeling studies using this general approach are expected to facilitate "scaffold hopping" and structure-guided elaborations of fragment-like kinase inhibitor cores.
Subject(s)
Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Isoquinolines/pharmacology , Magnetic Resonance Spectroscopy/methods , Models, Molecular , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Binding Sites/drug effects , Crystallography, X-Ray , Humans , Intracellular Signaling Peptides and Proteins/chemistry , Isoquinolines/chemistry , Magnetic Resonance Spectroscopy/standards , Molecular Structure , Protein Kinase Inhibitors/chemistry , Protein Serine-Threonine Kinases/chemistry , Protons , Reference Standards , Structure-Activity RelationshipABSTRACT
This study reports the identification and Hits to Leads optimization of inhibitors of coactivator associated arginine methyltransferase (CARM1). Compound 7b is a potent, selective inhibitor of CARM1.
Subject(s)
Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Pyrazoles/chemical synthesis , Pyrazoles/pharmacology , Combinatorial Chemistry Techniques , Molecular Structure , Pyrazoles/chemistry , Stereoisomerism , Structure-Activity RelationshipABSTRACT
An amide library derived from the pyrrolo[2,1-f][1,2,4]triazine scaffold led to the identification of modest inhibitors of Met kinase activity. Introduction of polar side chains at C-6 of the pyrrolotriazine core provided significant improvements in in vitro potency. The amide moiety could be replaced with acylurea and malonamide substituents to give compounds with improved potency in the Met-driven GTL-16 human gastric carcinoma cell line. Acylurea pyrrolotriazines with substitution at C-5 demonstrated single digit nanomolar kinase activity. X-ray crystallography revealed that the C-5 substituted pyrrolotriazines bind to the Met kinase domain in an ATP-competitive manner.
Subject(s)
Enzyme Inhibitors/pharmacology , Proto-Oncogene Proteins/antagonists & inhibitors , Pyrroles/chemistry , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Receptors, Growth Factor/antagonists & inhibitors , Stomach Neoplasms/drug therapy , Triazines/chemistry , Animals , Caco-2 Cells/drug effects , Cell Proliferation/drug effects , Cells, Cultured/drug effects , Crystallography, X-Ray , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Glutathione Transferase/antagonists & inhibitors , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Mice , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Molecular Structure , Protein Conformation , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-met , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/metabolism , Stomach Neoplasms/blood , Stomach Neoplasms/enzymology , Structure-Activity RelationshipABSTRACT
K(V)1.5 blockers have the potential to be atrium-selective agents for treatment of atrial fibrillation. The benzopyrans provide a template for the synthesis of potent and selective K(V)1.5 blockers.
Subject(s)
Atrial Fibrillation/drug therapy , Atrial Function/drug effects , Benzopyrans/pharmacology , Kv1.5 Potassium Channel/drug effects , Potassium Channel Blockers/pharmacology , Sulfonamides/pharmacology , Atrial Function/physiology , Benzopyrans/chemistry , Kv1.5 Potassium Channel/metabolism , Models, Chemical , Potassium Channel Blockers/chemical synthesis , Sulfonamides/chemistryABSTRACT
Among the several goals of a high-throughput screening campaign is the identification of as many active chemotypes as possible for further evaluation. Often, however, the number of concentration response curves (e.g., IC(50)s or K(i)s) that can be collected following a primary screen is limited by practical constraints such as protein supply, screening workload, and so forth. One possible approach to this dilemma is to cluster the hits from the primary screen and sample only a few compounds from each cluster. This introduces the question as to how many compounds must be selected from a cluster to ensure that an active compound is identified, if it exists at all. This article seeks to address this question using a Monte Carlo simulation in which the dependence of the success of sampling is directly linked to screening data variability. Furthermore, the authors demonstrate that the use of replicated compounds in the screening collection can easily assess this variability and provide a priori guidance to the screener and chemist as to the extent of sampling required to maximize chemotype identification during the triage process. The individual steps of the Monte Carlo simulation provide insight into the correspondence between the percentage inhibition and eventual IC(50) curves.
Subject(s)
Drug Evaluation, Preclinical/methods , Protein Kinases/analysis , Receptor Protein-Tyrosine Kinases/analysis , Receptors, G-Protein-Coupled/analysis , Adenosine Triphosphate/metabolism , Biocompatible Materials/chemistry , Biotinylation , Cluster Analysis , Computer Simulation , Coumarins/metabolism , Fluorescein , Fluorescence Resonance Energy Transfer , Fluorescent Dyes , Inhibitory Concentration 50 , Monte Carlo Method , Polystyrenes/chemistry , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Receptors, G-Protein-Coupled/antagonists & inhibitors , Sampling Studies , Scintillation Counting/methods , Software Design , Spectrophotometry , Wheat Germ Agglutinins/chemistryABSTRACT
A new class of lymphocyte function-associated antigen-1 (LFA-1) antagonists is described. Elaboration of the 2,3-dihydro-1H-pyrrolizin-5(7aH)-one scaffold resulted in the synthesis of potent inhibitors of the LFA-1/ICAM-1 interaction. Along with the in vitro activity, we present the X-ray crystal structure of the complex of compound 9b, in a novel binding mode to the I-domain of LFA-1.
Subject(s)
Chemistry, Pharmaceutical/methods , Lymphocyte Function-Associated Antigen-1/chemistry , Pyrroles/chemistry , Crystallography, X-Ray , Drug Design , Drug Screening Assays, Antitumor , HeLa Cells , Humans , Inhibitory Concentration 50 , Models, Chemical , Molecular Conformation , Stereoisomerism , Temperature , X-RaysABSTRACT
The design, synthesis, and SAR studies of 'core' variations led to identification of novel, selective, and potent small molecule antagonist (22) of the CC chemokine receptor-4 (CCR4) with improved in vitro activity and liability profile. Compound 22 was efficacious in a murine allergic inflammation model (ED50 approximately 10 mg/kg).
Subject(s)
Receptors, Chemokine/antagonists & inhibitors , Animals , Benzyl Compounds/chemical synthesis , Benzyl Compounds/pharmacology , Cell Line , Chemotaxis/drug effects , Dose-Response Relationship, Drug , Indicators and Reagents , Mice , Ovalbumin , Pneumonia/chemically induced , Pneumonia/drug therapy , Quinolines/chemical synthesis , Quinolines/pharmacology , Receptors, CCR4 , Respiratory Hypersensitivity/drug therapy , Respiratory Hypersensitivity/pathology , Structure-Activity RelationshipABSTRACT
In a high-throughput screening effort, a series of tetrahydroisoquinolines was identified as modest inhibitors of human Eg5. A medicinal chemistry optimization effort led to the identification of R-4-(3-hydroxyphenyl)-N,N-7,8-tetramethyl-3,4-dihydroisoquinoline-2(1H)-carboxamide (32a) as a potent inhibitor of human Eg5 (ATPase IC50 104 nM) with good anti-proliferative activity in A2780 cells (IC50 234 nM).