ABSTRACT
Selective inhibitors of DYRK1A are of interest for the treatment of cancer, Type 2 diabetes and neurological disorders. Optimization of imidazo [1,2-b]pyridazine fragment 1 through structure-activity relationship exploration and in silico drug design efforts led to the discovery of compound 17 as a potent cellular inhibitor of DYRK1A with selectivity over much of the kinome. The binding mode of compound 17 was elucidated with X-ray crystallography, facilitating the rational design of compound 29, an imidazo [1,2-b]pyridazine with improved kinase selectivity with respect to closely related CLK kinases.
Subject(s)
Diabetes Mellitus, Type 2 , Iohexol/analogs & derivatives , Pyridazines , Humans , Dyrk Kinases , Diabetes Mellitus, Type 2/drug therapy , Protein Kinase Inhibitors/chemistry , Structure-Activity Relationship , Pyridazines/chemistryABSTRACT
Dual-specificity tyrosine-regulated kinase 1A (DYRK1A) regulates the proliferation and differentiation of neuronal progenitor cells during brain development. Consequently, DYRK1A has attracted interest as a target for the treatment of neurodegenerative diseases, including Alzheimer's disease (AD) and Down's syndrome. Recently, the inhibition of DYRK1A has been investigated as a potential treatment for diabetes, while DYRK1A's role as a mediator in the cell cycle has garnered interest in oncologic indications. Structure-activity relationship (SAR) analysis in combination with high-resolution X-ray crystallography leads to a series of pyrazolo[1,5-b]pyridazine inhibitors with excellent ligand efficiencies, good physicochemical properties, and a high degree of selectivity over the kinome. Compound 11 exhibited good permeability and cellular activity without P-glycoprotein liability, extending the utility of 11 in an in vivo setting. These pyrazolo[1,5-b]pyridazines are a viable lead series in the discovery of new therapies for the treatment of diseases linked to DYRK1A function.
Subject(s)
Drug Discovery , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Dose-Response Relationship, Drug , HEK293 Cells , Humans , Ligands , Molecular Structure , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/metabolism , Solubility , Structure-Activity Relationship , Dyrk KinasesABSTRACT
Kinases represent one of the most intensively pursued groups of targets in modern-day drug discovery. Often it is desirable to achieve selective inhibition of the kinase of interest over the remaining â¼500 kinases in the human kinome. This is especially true when inhibitors are intended to be used to study the biology of the target of interest. We present a pipeline of open-source software that analyzes public domain data to repurpose compounds that have been used in previous kinase inhibitor development projects. We define the dual-specificity tyrosine-regulated kinase 1A (DYRK1A) as the kinase of interest, and by addition of a single methyl group to the chosen starting point we remove glycogen synthase kinase ß (GSK3ß) and cyclin-dependent kinase (CDK) inhibition. Thus, in an efficient manner we repurpose a GSK3ß/CDK chemotype to deliver 8b, a highly selective DYRK1A inhibitor.
ABSTRACT
The halodecarboxylation of heteroarene carboxylic acids by treatment with N-bromosuccinimide or N-chlorosuccinimide was performed. This procedure provides a convenient route to synthetically useful mono-halogenated heteroarene intermediates such as halo-indoles, -aza-indoles, -indazoles and -aza-indazoles. The mild conditions employed and simple protocol provides an advantage over traditional halodecarboxylation procedures that require expensive and toxic metal catalysts, basic conditions, time-consuming intermediate isolation and elevated reaction temperatures.