RESUMO
A high throughput screening campaign identified 5-(2-chlorophenyl)indazole compound 4 as an antagonist of the transient receptor potential A1 (TRPA1) ion channel with IC50 = 1.23 µM. Hit to lead medicinal chemistry optimization established the SAR around the indazole ring system, demonstrating that a trifluoromethyl group at the 2-position of the phenyl ring in combination with various substituents at the 6-position of the indazole ring greatly contributed to improvements in vitro activity. Further lead optimization resulted in the identification of compound 31, a potent and selective antagonist of TRPA1 in vitro (IC50 = 0.015 µM), which has moderate oral bioavailability in rodents and demonstrates robust activity in vivo in several rodent models of inflammatory pain.
Assuntos
Indazóis/química , Proteínas do Tecido Nervoso/antagonistas & inibidores , Canais de Potencial de Receptor Transitório/antagonistas & inibidores , Administração Oral , Analgésicos/química , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Disponibilidade Biológica , Células CHO , Canais de Cálcio , Cricetulus , Adjuvante de Freund , Humanos , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Indazóis/farmacocinética , Indazóis/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Mostardeira , Óleos de Plantas , Ratos Wistar , Especificidade da Espécie , Relação Estrutura-Atividade , Canal de Cátion TRPA1 , Canais de Cátion TRPC/antagonistas & inibidoresRESUMO
A series of peptidic fluorogenic substrates were synthesized to develop a flow cytometry assay (FACS) to monitor the proteolytic activity of cathepsin C in live cells. Of the 16 substrates tested, (NH(2)-aminobutyric-homophenylalanine)(2)-rhodamine demonstrated the best reactivity and selectivity profile in the FACS assay using the B721 human B-lymphoblastoid cell line. The resulting FACS assay was validated through correlation of the IC(50) values with a competitive radiolabeling assay against a series of small molecule inhibitors of cathepsin C.
Assuntos
Catepsina C/metabolismo , Corantes Fluorescentes/química , Rodaminas/química , Catepsina C/antagonistas & inibidores , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Marcação por Isótopo , Radioisótopos/química , Rodaminas/síntese química , Especificidade por SubstratoRESUMO
The synthesis and structure-activity relationship of a series of arylaminoethyl amide cathepsin S inhibitors are reported. Optimization of P3 and P2 groups to improve overall physicochemical properties resulted in significant improvements in oral bioavailability over early lead compounds. An X-ray structure of compound 37 bound to the active site of cathepsin S is also reported.
Assuntos
Amidas/síntese química , Amidas/farmacologia , Catepsinas/antagonistas & inibidores , Administração Oral , Amidas/farmacocinética , Animais , Sítios de Ligação , Disponibilidade Biológica , Cristalografia por Raios X , Éteres Cíclicos/síntese química , Éteres Cíclicos/farmacologia , Humanos , Masculino , Estrutura Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacocinética , Inibidores de Proteases/farmacologia , Ratos , Ratos Wistar , Relação Estrutura-Atividade , ZincoRESUMO
A strategy was developed to determine the prime and non-prime substrate specificity of serine, threonine and cysteine proteases. ACC positional scanning technology was employed to determine the P4-P1 non-prime site substrate specificity. The data was used to synthesize biased donor-quencher positional scanning libraries to profile the P1'-P4' prime site substrate specificity. Directed sorting using the Irori Nanokan system allowed for the archiving of multiple P1'-P4' positional scanning libraries. From these libraries focused donor-quencher libraries incorporating P4-P1 data for each protease under study could be rapidly prepared. The profiling of thrombin and caspase-3 P4-P4' substrate specificity, comparison of the library specificity data to single substrates, and the analysis of physiological cleavage sites are described.