ABSTRACT
Development of a series of highly kinome-selective spleen tyrosine kinase (Syk) inhibitors with favorable druglike properties is described. Early leads were discovered through X-ray crystallographic analysis, and a systematic survey of cores within a selected chemical space focused on ligand binding efficiency. Attenuation of hERG ion channel activity inherent within the initial chemotype was guided through modulation of physicochemical properties including log D, PSA, and pKa. PSA proved most effective for prospective compound design. Further profiling of an advanced compound revealed bacterial mutagenicity in the Ames test using TA97a Salmonella strain, and subsequent study demonstrated that this mutagenicity was pervasive throughout the series. Identification of intercalation as a likely mechanism for the mutagenicity-enabled modification of the core scaffold. Implementation of a DNA binding assay as a prescreen and models in DNA allowed resolution of the mutagenicity risk, affording molecules with favorable potency, selectivity, pharmacokinetic, and off-target profiles.
Subject(s)
Amides/pharmacology , Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Spleen/enzymology , Amides/chemical synthesis , Amides/chemistry , Crystallography, X-Ray , Dose-Response Relationship, Drug , Ether-A-Go-Go Potassium Channels/genetics , Ether-A-Go-Go Potassium Channels/metabolism , Humans , Models, Molecular , Molecular Structure , Mutagenicity Tests , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Protein-Tyrosine Kinases/metabolism , Spleen/drug effects , Structure-Activity RelationshipABSTRACT
Histone deacetylase 5 (HDAC5) represses expression of nuclear genes that promote cardiac hypertrophy. Agonism of a variety of G protein coupled receptors (GPCRs) triggers phosphorylation-dependent nuclear export of HDAC5 via the CRM1 nuclear export receptor, resulting in derepression of pro-hypertrophic genes. A cell-based high-throughput screen of a commercial compound collection was employed to identify compounds with the ability to preserve the nuclear fraction of GFP-HDAC5 in primary cardiomyocytes exposed to GPCR agonists. A hit compound potently inhibited agonist-induced GFP-HDAC5 nuclear export in cultured neonatal rat ventricular myocytes (NRVMs). A small set of related compounds was designed and synthesized to evaluate structure-activity relationship (SAR). The results demonstrated that inhibition of HDAC5 nuclear export was a result of compounds irreversibly reacting with a key cysteine residue in CRM1 that is required for its function. CRM1 inhibition by the compounds also resulted in potent suppression of cardiomyocyte hypertrophy. These studies define a novel class of anti-hypertrophic compounds that function through irreversible inhibition of CRM1-dependent nuclear export.
Subject(s)
Cardiomegaly/drug therapy , Histone Deacetylases/metabolism , Karyopherins/antagonists & inhibitors , Myocytes, Cardiac/drug effects , Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors , Active Transport, Cell Nucleus/drug effects , Amides/pharmacology , Aniline Compounds/pharmacology , Animals , Cardiomegaly/metabolism , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Cells, Cultured , Histone Deacetylase Inhibitors , Histone Deacetylases/chemistry , Humans , Karyopherins/metabolism , Microscopy, Fluorescence , Myocytes, Cardiac/metabolism , Phosphorylation , Rats , Rats, Sprague-Dawley , Receptors, Cytoplasmic and Nuclear/metabolism , Structure-Activity Relationship , Exportin 1 ProteinABSTRACT
An SAR study of an HTS screening hit generated a series of pyridodiazepine amines as potent inhibitors of Helicobacter pylori glutamate racemase (MurI) showing highly selective anti-H. pylori activity, marked improved solubility, and reduced plasma protein binding. X-ray co-crystal E-I structures were obtained. These uncompetitive inhibitors bind at the MurI dimer interface.
Subject(s)
Amines/chemistry , Amino Acid Isomerases/chemistry , Chemistry, Pharmaceutical/methods , Helicobacter Infections/drug therapy , Helicobacter pylori/enzymology , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Binding, Competitive , Dimerization , Drug Design , Humans , Inhibitory Concentration 50 , Mice , Molecular Conformation , Structure-Activity RelationshipABSTRACT
The synthesis of louisianin C (3), a member of a small family of 3,4,5-trisubstituted pyridyl natural products, is achieved in six steps and 11% overall yield starting from commercially available 3,5-dibromopyridine. The key step is a fluoride-induced desilylation-cyclization to afford carbinol 12.
