ABSTRACT
Optimization of the potency and pharmacokinetic profile of 2,3,4-trisubstituted quinoline, 4, led to the discovery of two potent, selective, and orally bioavailable PI3Kδ inhibitors, 6a (AM-0687) and 7 (AM-1430). On the basis of their improved profile, these analogs were selected for in vivo pharmacodynamic (PD) and efficacy experiments in animal models of inflammation. The in vivo PD studies, which were carried out in a mouse pAKT inhibition animal model, confirmed the observed potency of 6a and 7 in biochemical and cellular assays. Efficacy experiments in a keyhole limpet hemocyanin model in rats demonstrated that administration of either 6a or 7 resulted in a strong dose-dependent reduction of IgG and IgM specific antibodies. The excellent in vitro and in vivo profiles of these analogs make them suitable for further development.
Subject(s)
Drug Discovery , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , Pyridines/pharmacology , Quinolines/pharmacology , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Class Ia Phosphatidylinositol 3-Kinase/metabolism , Dose-Response Relationship, Drug , Humans , Mice , Models, Molecular , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Pyridines/chemical synthesis , Pyridines/chemistry , Quinolines/chemical synthesis , Quinolines/chemistry , Structure-Activity RelationshipABSTRACT
Lead optimization efforts resulted in the discovery of two potent, selective, and orally bioavailable PI3Kδ inhibitors, 1 (AM-8508) and 2 (AM-9635), with good pharmacokinetic properties. The compounds inhibit B cell receptor (BCR)-mediated AKT phosphorylation (pAKT) in PI3Kδ-dependent in vitro cell based assays. These compounds which share a benzimidazole bicycle are effective when administered in vivo at unbound concentrations consistent with their in vitro cell potency as a consequence of improved unbound drug concentration with lower unbound clearance. Furthermore, the compounds demonstrated efficacy in a Keyhole Limpet Hemocyanin (KLH) study in rats, where the blockade of PI3Kδ activity by inhibitors 1 and 2 led to effective inhibition of antigen-specific IgG and IgM formation after immunization with KLH.
Subject(s)
Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/pharmacology , Animals , B-Lymphocytes/drug effects , Crystallography, X-Ray , Hemocyanins/drug effects , Humans , Immunoglobulin G/drug effects , Immunoglobulin M/drug effects , Mice , Models, Molecular , Rats , Structure-Activity RelationshipABSTRACT
The development and optimization of a series of quinolinylpurines as potent and selective PI3Kδ kinase inhibitors with excellent physicochemical properties are described. This medicinal chemistry effort led to the identification of 1 (AMG319), a compound with an IC50 of 16 nM in a human whole blood assay (HWB), excellent selectivity over a large panel of protein kinases, and a high level of in vivo efficacy as measured by two rodent disease models of inflammation.
Subject(s)
Adenosine/pharmacology , Autoimmune Diseases/prevention & control , Class I Phosphatidylinositol 3-Kinases/antagonists & inhibitors , Inflammation/prevention & control , Protein Kinase Inhibitors/pharmacology , Quinolines/pharmacology , Adenosine/chemistry , Adenosine/metabolism , Animals , Cells, Cultured , Class I Phosphatidylinositol 3-Kinases/chemistry , Class I Phosphatidylinositol 3-Kinases/metabolism , Crystallography, X-Ray , Disease Models, Animal , Drug Discovery , Female , Humans , Mice, Inbred BALB C , Mice, Transgenic , Models, Chemical , Models, Molecular , Molecular Structure , Protein Binding , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Structure, Tertiary , Quinolines/chemistry , Quinolines/metabolism , Rats, Inbred Lew , Sf9 Cells , Structure-Activity RelationshipABSTRACT
Structure-based rational design and extensive structure-activity relationship studies led to the discovery of AMG 232 (1), a potent piperidinone inhibitor of the MDM2-p53 association, which is currently being evaluated in human clinical trials for the treatment of cancer. Further modifications of 1, including replacing the carboxylic acid with a 4-amidobenzoic acid, afforded AM-7209 (25), featuring improved potency (KD from ITC competition was 38 pM, SJSA-1 EdU IC50 = 1.6 nM), remarkable pharmacokinetic properties, and in vivo antitumor activity in both the SJSA-1 osteosarcoma xenograft model (ED50 = 2.6 mg/kg QD) and the HCT-116 colorectal carcinoma xenograft model (ED50 = 10 mg/kg QD). In addition, 25 possesses distinct mechanisms of elimination compared to 1.
Subject(s)
Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Colonic Neoplasms/drug therapy , Drug Discovery , Protein Binding/drug effects , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Tumor Suppressor Protein p53/antagonists & inhibitors , Animals , Antineoplastic Agents/chemistry , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Female , Humans , Mice , Mice, Nude , Models, Molecular , Molecular Structure , Proto-Oncogene Proteins c-mdm2/metabolism , Structure-Activity Relationship , Tumor Cells, Cultured , Tumor Suppressor Protein p53/metabolismABSTRACT
We describe the structural optimization of a lead compound 1 that exhibits dual inhibitory activities against FLT3 and CDK4. A series of pyrido[4',3':4,5]pyrrolo[2,3-d]pyrimidine derivatives was synthesized, and SAR analysis, using cell-based assays, led to the discovery of 28 (AMG 925), a potent and orally bioavailable dual inhibitor of CDK4 and FLT3, including many FLT3 mutants reported to date. Compound 28 inhibits the proliferation of a panel of human tumor cell lines including Colo205 (Rb(+)) and U937 (FLT3(WT)) and induced cell death in MOLM13 (FLT3(ITD)) and even in MOLM13 (FLT3(ITD, D835Y)), which exhibits resistance to a number of FLT3 inhibitors currently under clinical development. At well-tolerated doses, compound 28 leads to significant growth inhibition of MOLM13 xenografts in nude mice, and the activity correlates with inhibition of STAT5 and Rb phosphorylation.
Subject(s)
Cyclin-Dependent Kinase 4/antagonists & inhibitors , Heterocyclic Compounds, 3-Ring/chemical synthesis , Naphthyridines/chemical synthesis , Protein Kinase Inhibitors/chemical synthesis , fms-Like Tyrosine Kinase 3/antagonists & inhibitors , Animals , Cyclin-Dependent Kinase 6/antagonists & inhibitors , Cytochrome P-450 CYP3A , Cytochrome P-450 CYP3A Inhibitors , Dogs , Drug Discovery , Heterocyclic Compounds, 3-Ring/pharmacology , Humans , Macaca fascicularis , Naphthyridines/pharmacology , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/pharmacology , Rats , Structure-Activity Relationship , U937 Cells , fms-Like Tyrosine Kinase 3/geneticsABSTRACT
We previously reported the discovery of potent and selective morpholinone and piperidinone inhibitors of the MDM2-p53 interaction. These inhibitors have in common a carboxylic acid moiety that engages in an electrostatic interaction with MDM2-His96. Our continued search for potent and diverse inhibitors led to the discovery of novel replacements for these acids uncovering new interactions with the MDM2 protein. In particular, using pyridine or thiazole as isosteres of the carboxylic acid moiety resulted in very potent analogues. From these, AM-6761 (4) emerged as a potent inhibitor with remarkable biochemical (HTRF IC50 = 0.1 nM) and cellular potency (SJSA-1 EdU IC50 = 16 nM), as well as favorable pharmacokinetic properties. Compound 4 also shows excellent antitumor activity in the SJSA-1 osteosarcoma xenograft model with an ED50 of 11 mg/kg. Optimization efforts toward the discovery of these inhibitors as well as the new interactions observed with the MDM2 protein are described herein.
Subject(s)
Acetates/pharmacology , Antineoplastic Agents/pharmacology , Carboxylic Acids/pharmacology , Cell Proliferation/drug effects , Myocytes, Smooth Muscle/drug effects , Piperidones/pharmacology , Protein Interaction Domains and Motifs/drug effects , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Tumor Suppressor Protein p53/antagonists & inhibitors , Acetates/chemistry , Animals , Bone Neoplasms/drug therapy , Carboxylic Acids/chemistry , Cells, Cultured , Crystallography, X-Ray , Drug Design , Female , Humans , Hydrogen Bonding , Mice , Mice, Nude , Models, Molecular , Molecular Structure , Osteosarcoma/drug therapy , Piperidones/chemistry , Protein Binding , Proto-Oncogene Proteins c-mdm2/metabolism , Stereoisomerism , Structure-Activity Relationship , Tumor Cells, Cultured , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor AssaysABSTRACT
We previously reported the discovery of AMG 232, a highly potent and selective piperidinone inhibitor of the MDM2-p53 interaction. Our continued search for potent and diverse analogues led to the discovery of novel morpholinone MDM2 inhibitors. This change to a morpholinone core has a significant impact on both potency and metabolic stability compared to the piperidinone series. Within this morpholinone series, AM-8735 emerged as an inhibitor with remarkable biochemical potency (HTRF IC50 = 0.4 nM) and cellular potency (SJSA-1 EdU IC50 = 25 nM), as well as pharmacokinetic properties. Compound 4 also shows excellent antitumor activity in the SJSA-1 osteosarcoma xenograft model with an ED50 of 41 mg/kg. Lead optimization toward the discovery of this inhibitor as well as key differences between the morpholinone and the piperidinone series will be described herein.
Subject(s)
Acetates/chemical synthesis , Acetates/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Morpholines/chemical synthesis , Morpholines/pharmacology , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Proto-Oncogene Proteins c-mdm2/chemistry , Tumor Suppressor Protein p53/antagonists & inhibitors , Tumor Suppressor Protein p53/chemistry , Animals , Cell Line, Tumor , Crystallography, X-Ray , Drug Discovery , Humans , Indicators and Reagents , Mice , Models, Molecular , Molecular Conformation , Morpholines/pharmacokinetics , Rats , Structure-Activity Relationship , Xenograft Model Antitumor AssaysABSTRACT
We recently reported the discovery of AM-8553 (1), a potent and selective piperidinone inhibitor of the MDM2-p53 interaction. Continued research investigation of the N-alkyl substituent of this series, focused in particular on a previously underutilized interaction in a shallow cleft on the MDM2 surface, led to the discovery of a one-carbon tethered sulfone which gave rise to substantial improvements in biochemical and cellular potency. Further investigation produced AMG 232 (2), which is currently being evaluated in human clinical trials for the treatment of cancer. Compound 2 is an extremely potent MDM2 inhibitor (SPR KD = 0.045 nM, SJSA-1 EdU IC50 = 9.1 nM), with remarkable pharmacokinetic properties and in vivo antitumor activity in the SJSA-1 osteosarcoma xenograft model (ED50 = 9.1 mg/kg).
Subject(s)
Acetates/pharmacology , Antineoplastic Agents/pharmacology , Piperidones/pharmacology , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Tumor Suppressor Protein p53/antagonists & inhibitors , Acetates/chemistry , Administration, Oral , Antineoplastic Agents/chemistry , Biological Availability , Crystallography, X-Ray , Drug Discovery , Humans , Piperidones/chemistry , Protein ConformationABSTRACT
The discovery and initial optimization of a series of phenylalanine based agonists for GPR142 is described. The structure-activity-relationship around the major areas of the molecule was explored to give agonists 90 times more potent than the initial HTS hit in a human GPR142 inositol phosphate accumulation assay. Removal of CYP inhibition by exploration of the pyridine A-ring is also described.
Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Drug Discovery , Hypoglycemic Agents/pharmacology , Phenylalanine/pharmacology , Receptors, G-Protein-Coupled/agonists , Animals , Dose-Response Relationship, Drug , Humans , Hypoglycemic Agents/chemical synthesis , Hypoglycemic Agents/chemistry , Microsomes, Liver/chemistry , Microsomes, Liver/metabolism , Molecular Structure , Phenylalanine/chemical synthesis , Phenylalanine/chemistry , Rats , Structure-Activity RelationshipABSTRACT
The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3 receptor is reported. Compounds were optimized to avoid the formation of active metabolites and time-dependent-inhibitors of CYP3A4. In addition, antagonists showed potent against CXCR3 activity in whole blood and optimized to avoid activity in the chromosomal aberration assay. Compound 25 was identified as having the optimal balance of CXCR3 activity and pharmacokinetic properties across multiple pre-clinical species, which are reported herein.
Subject(s)
Quinazolines/chemical synthesis , Quinazolinones/chemical synthesis , Receptors, CXCR3/antagonists & inhibitors , Animals , Bleomycin/toxicity , Chromosome Aberrations , Cytochrome P-450 CYP3A , Cytochrome P-450 CYP3A Inhibitors , Dogs , Dose-Response Relationship, Drug , Drug Design , Humans , Inflammation , Inhibitory Concentration 50 , Leukocytes/drug effects , Macaca fascicularis , Mice , Models, Chemical , Quinazolines/pharmacology , Quinazolinones/pharmacology , Time FactorsABSTRACT
A general way of improving the potency of CXCR3 antagonists with fused hetero-bicyclic cores was identified. Optimization efforts led to the discovery of a series of imidazo-pyrazine derivatives with improved pharmacokinetic properties in addition to increased potency. The efficacy of the lead compound 21 is evaluated in a mouse lung inflammation model.
Subject(s)
Anti-Inflammatory Agents/chemistry , Benzeneacetamides/chemistry , Cyclic S-Oxides/chemistry , Imidazoles/chemistry , Pyrazines/chemistry , Receptors, CXCR3/antagonists & inhibitors , Animals , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/pharmacokinetics , Benzeneacetamides/chemical synthesis , Benzeneacetamides/pharmacokinetics , Cyclic S-Oxides/chemical synthesis , Cyclic S-Oxides/pharmacokinetics , Humans , Imidazoles/chemical synthesis , Imidazoles/pharmacokinetics , Mice , Molecular Conformation , Pyrazines/chemical synthesis , Pyrazines/pharmacokinetics , Rats , Receptors, CXCR3/metabolismABSTRACT
A series of imidazole derivatives have been designed and optimized for CXCR3 antagonism, pharmacokinetic properties, and reduced formation of glutathione conjugates. Our efforts led to the discovery of potent CXCR3 antagonists with good pharmacokinetic properties. These compounds are useful tools for in vivo studies of CXCR3 function.
Subject(s)
Imidazoles/chemistry , Imidazoles/pharmacology , Receptors, CXCR3/antagonists & inhibitors , Animals , Chromatography, High Pressure Liquid , Drug Design , Humans , Imidazoles/pharmacokinetics , Mice , Mice, Knockout , Rats , Receptors, CXCR3/genetics , Receptors, CXCR3/physiology , Structure-Activity RelationshipABSTRACT
A series of six-six and six-five fused heterocyclic CXCR3 antagonists has been synthesized and their activities evaluated in an [(125)I]-IP-10 displacement assay and an ITAC mediated in vitro cell migration assay. The pharmacokinetic properties of several top compounds have also been studied. This effort led to the discovery of compounds with increased potency and improved pharmacokinetic properties that could serve as useful tools to study the role of the CXCR3 receptor in vivo.
Subject(s)
Heterocyclic Compounds/pharmacology , Quinazolinones/pharmacology , Receptors, CXCR3/antagonists & inhibitors , Animals , Chromatography, High Pressure Liquid , Humans , Quinazolinones/pharmacokinetics , Rats , StereoisomerismABSTRACT
We have developed a modification of the Miyaura arylboronate synthesis(1a) by substituting a ligandless palladium catalyst for PdCl(2)(dppf). Palladium acetate, free of ligand, was found highly effective for such coupling reactions. This modified procedure is advantageous over the original Miyaura synthesis in ease of workup, catalyst removal, and low catalyst cost. Furthermore, the boronates formed in this manner can be used directly for Suzuki coupling reactions in a one-pot fashion. The biaryl products have improved impurity profiles and reduced heavy metal contamination.