RESUMO
Previously we have described a novel series of potent and selective A 2A receptor antagonists (e.g., 1) with excellent aqueous solubility. While these compounds are efficacious A 2A antagonists in vivo, the presence of an unsubstituted furyl moiety was a cause of some concern. In order to avoid the potential metabolic liabilities that could arise from an unsubstituted furyl moiety, an optimization effort was undertaken with the aim of replacing the unsubstituted furan with a more metabolically stable group while maintaining potency and selectivity. Herein, we describe the synthesis and SAR of a range of novel heterocyclic systems and the successful identification of a replacement for the unsubstituted furan moiety with a methylfuran or thiazole moiety while maintaining potency and selectivity.
Assuntos
Acetamidas/síntese química , Acetamidas/farmacologia , Antagonistas do Receptor A2 de Adenosina , Pirimidinas/síntese química , Pirimidinas/farmacologia , Acetamidas/química , Animais , Sítios de Ligação , Ciclização , Avaliação Pré-Clínica de Medicamentos , Hepatócitos/efeitos dos fármacos , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Pirimidinas/química , Ratos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Previously we have described a series of novel A 2A receptor antagonists with excellent water solubility. As described in the accompanying paper, the antagonists were first optimized to remove an unsubstituted furyl moiety, with the aim of avoiding the potential metabolic liabilities that can arise from the presence of an unsubstituted furan. This effort identified a series of potent and selective methylfuryl derivatives. Herein, we describe the further optimization of this series to increase potency, maintain selectivity for the human A 2A vs the human A 1 receptor, and minimize activity against the hERG channel. In addition, the observed structure-activity relationships against both the human and the rat A 2A receptor are reported.
Assuntos
Acetamidas/farmacologia , Antagonistas do Receptor A2 de Adenosina , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Pirimidinas/farmacologia , Acetamidas/síntese química , Acetamidas/química , Antagonistas do Receptor A1 de Adenosina , Animais , Avaliação Pré-Clínica de Medicamentos , Canais de Potássio Éter-A-Go-Go/metabolismo , Hepatócitos/efeitos dos fármacos , Humanos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Ratos , Ratos Wistar , Especificidade da Espécie , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A series of N-pyrimidinyl-2-phenoxyacetamide adenosine A(2A) antagonists is described. SAR studies led to compound 14 with excellent potency (K(i) = 0.4 nM), selectivity (A(1)/A(2A) > 100), and efficacy (MED 10 mg/kg p.o.) in the rat haloperidol-induced catalepsy model for Parkinson's disease.
Assuntos
Antagonistas do Receptor A2 de Adenosina , Antiparkinsonianos/síntese química , Catalepsia/prevenção & controle , Doença de Parkinson/fisiopatologia , Fenoxiacetatos/síntese química , Pirimidinas/síntese química , Administração Oral , Animais , Antiparkinsonianos/farmacologia , Catalepsia/induzido quimicamente , Citocromo P-450 CYP2D6/metabolismo , Inibidores do Citocromo P-450 CYP2D6 , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Eletrofisiologia , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Haloperidol/toxicidade , Humanos , Estrutura Molecular , Fenoxiacetatos/química , Fenoxiacetatos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Ratos , Relação Estrutura-AtividadeRESUMO
In this report, the design and synthesis of a series of pyrimidine based adenosine A(2A) antagonists are described. The strategy and outcome of expanding SAR exploration to attenuate hERG and improve selectivity over A(1) are discussed. Compound 33 exhibited excellent potency, selectivity over A(1), and reduced hERG liability.
Assuntos
Antagonistas do Receptor A2 de Adenosina , Proteínas de Ligação a DNA/antagonistas & inibidores , Pirimidinas/farmacologia , Transativadores/antagonistas & inibidores , Linhagem Celular , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A , Desenho de Fármacos , Humanos , Cinética , Pirimidinas/síntese química , Pirimidinas/química , Receptor A2A de Adenosina/metabolismo , Relação Estrutura-Atividade , Regulador Transcricional ERGRESUMO
Potent adenosine hA2A receptor antagonists are often accompanied by poor aqueous solubility, which presents issues for drug development. Herein we describe the early exploration of the structure-activity relationships of a lead pyrimidin-4-yl acetamide series to provide potent and selective 2-amino-N-pyrimidin-4-yl acetamides as hA2A receptor antagonists with excellent aqueous solubility. In addition, this series of compounds has demonstrated good bioavailability and in vivo efficacy in a rodent model of Parkinson's disease, despite having reduced potency for the rat A2A receptor versus the human A2A receptor.
Assuntos
Acetamidas/síntese química , Antagonistas do Receptor A2 de Adenosina , Antiparkinsonianos/síntese química , Pirimidinas/síntese química , Acetamidas/farmacocinética , Acetamidas/farmacologia , Animais , Antiparkinsonianos/farmacocinética , Antiparkinsonianos/farmacologia , Catalepsia/induzido quimicamente , Catalepsia/psicologia , Linhagem Celular , Clonagem Molecular , Cricetinae , Cricetulus , Haloperidol , Humanos , Técnicas In Vitro , Masculino , Microssomos Hepáticos/metabolismo , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ensaio Radioligante , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Receptor A2A de Adenosina/genética , Solubilidade , Relação Estrutura-Atividade , ÁguaRESUMO
The human genome encodes five nonpolymorphic major histocompatibility complex class I-like glycoproteins, CD1a to CD1e, that present lipid antigens for specific recognition by T lymphocytes. Using single alkyl chain detergents, we developed a protocol to generate recombinant human CD1b-lipid complexes. We present here the crystal structures of CD1b in complex with either phosphatidylinositol or ganglioside GM2 at 2.3 A and 2.8 A resolutions, respectively. The antigen-binding groove houses four interlinked hydrophobic channels that are occupied by the alkyl chains of the glycolipid plus two detergent molecules. A distinct exit beneath the alpha 2 helix further contributes to the plasticity of the binding groove. These structures reveal the mechanism by which two alkyl chain lipids bind to CD1b, and how CD1b can adapt to ligands of different alkyl chain length. They also suggest how very long alkyl chains, such as those of mycolic acid, could be fully contained within the binding groove. These results extend the spectrum of potential CD1b ligands by revealing that, in addition to two alkyl chain lipids, mono-alkyl and triple-alkyl chain lipids can be accommodated in the binding groove.