RESUMO
This Letter reports the optimization of a pyrrolopyrimidine series as dual inhibitors of Aurora A/B kinases. This series derived from a pyrazolopyrimidine series previously reported as inhibitors of aurora kinases and CDKs. In an effort to improve the selectivity of this chemotype, we switched to the pyrrolopyrimidine core which allowed functionalization on C-2. In addition, the modeling rationale was based on superimposing the structures of Aurora-A kinase and CDK2 which revealed enough differences leading to a path for selectivity improvement. The synthesis of the new series of pyrrolopyrimidine analogs relied on the development of a different route for the two key intermediates 7 and 19 which led to analogs with both tunable activity against CDK1 and maintained cell potency.
Assuntos
Antineoplásicos/síntese química , Proteína Quinase CDC2/química , Quinase 2 Dependente de Ciclina/química , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/síntese química , Pirróis/síntese química , Antineoplásicos/farmacologia , Aurora Quinases , Sítios de Ligação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Desenho de Fármacos , Humanos , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/química , Pirimidinas/farmacologia , Pirróis/farmacologia , Homologia Estrutural de Proteína , Relação Estrutura-AtividadeRESUMO
Since the early 2000s, the Aurora kinases have become major targets of oncology drug discovery particularly Aurora-A and Aurora-B kinases (AKA/AKB) for which the selective inhibition in cells lead to different phenotypes. In addition to targeting these Aurora kinases involved in mitosis, CDK1 has been added as a primary inhibition target in hopes of enhancing the cytotoxicity of our chemotypes harboring the pyrazolopyrimidine core. SAR optimization of this series using the AKA, AKB and CDK1 biochemical assays led to the discovery of the compound 7h which combines strong potency against the 3 kinases with an acceptable microsomal stability. Finally, switching from a primary amide to a two-substituted pyrrolidine amide gave rise to compound 15a which exhibited the desired AKA/CDK1 inhibition phenotype in cells but showed moderate activity in animal models using HCT116 tumor cell lines.
Assuntos
Proteína Quinase CDC2/antagonistas & inibidores , Neoplasias do Colo/tratamento farmacológico , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/química , Pirimidinas/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Aurora Quinase A , Aurora Quinase B , Aurora Quinases , Proteína Quinase CDC2/metabolismo , Linhagem Celular , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/patologia , Células HCT116 , Humanos , Camundongos , Modelos Moleculares , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Pirazóis/química , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos , Relação Estrutura-AtividadeRESUMO
In neutrophils, growth-related protein-alpha (CXCL1) and interleukin-8 (CXCL8), are potent chemoattractants (Cytokine 14:27-36, 2001; Biochemistry 42:2874-2886, 2003) and can stimulate myeloperoxidase release via activation of the G protein-coupled receptors CXCR1 and CXCR2. The role of CXCR1 and CXCR2 in the pathogenesis of inflammatory responses has encouraged the development of small molecule antagonists for these receptors. The data presented herein describe the pharmacology of 2-hydroxy-N,N-dimethyl-3-{2-[[(R)-1-(5-methyl-furan-2-yl)-propyl]amino]-3,4-dioxo-cyclobut-1-enylamino}-benzamide (Sch527123), a novel antagonist of both CXCR1 and CXCR2. Sch527123 inhibited chemokine binding to (and activation of) these receptors in an insurmountable manner and, as such, is categorized as an allosteric antagonist. Sch527123 inhibited neutrophil chemotaxis and myeloperoxidase release in response to CXCL1 and CXCL8 but had no effect on the response of these cells to C5a or formyl-methionyl-leucyl-phenylalanine. The pharmacological specificity of Sch527123 was confirmed by testing in a diversity profile against a panel of enzymes, channels, and receptors. To measure compound affinity, we characterized [(3)H]Sch527123 in both equilibrium and nonequilibrium binding analyses. Sch527123 binding to CXCR1 and CXCR2 was both saturable and reversible. Although Sch527123 bound to CXCR1 with good affinity (K(d) = 3.9 +/- 0.3 nM), the compound is CXCR2-selective (K(d) = 0.049 +/- 0.004 nM). Taken together, our data show that Sch527123 represents a novel, potent, and specific CXCR2 antagonist with potential therapeutic utility in a variety of inflammatory conditions.