RESUMO
An indole-based P1 moiety was incorporated into a previously established factor Xa inhibitor series. The indole group was designed to hydrogen-bond with the carbonyl of Gly218, while its 3-methyl or 3-chloro substituent was intended to interact with Tyr228. These interactions were subsequently observed in the X-ray crystal structure of compound 18. SAR studies led to the identification of compound 20 as the most potent FXa inhibitor in this series (IC(50) = 2.4 nM, EC(2xPT) = 1.2 microM). An in-depth energetic analysis suggests that the increased binding energy of 3-chloroindole-versus 3-methylindole-containing compounds in this series is due primarily to (a) the more hydrophobic nature of chloro- versus methyl-containing compounds and (b) an increased interaction of 3-chloroindole versus 3-methylindole with Gly218 backbone. The stronger hydrophobicity of chloro- versus methyl-substituted aromatics may partly explain the general preference for chloro- versus methyl-substituted P1 groups in FXa, which extends beyond the current series.
Assuntos
Desenho de Fármacos , Inibidores Enzimáticos , Inibidores do Fator Xa , Indóis , Teoria Quântica , Animais , Sítios de Ligação/efeitos dos fármacos , Simulação por Computador , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fator Xa/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Indóis/síntese química , Indóis/química , Indóis/farmacologia , Camundongos , Modelos Químicos , Modelos Moleculares , Relação Estrutura-Atividade , Análise de Sobrevida , Peçonhas/farmacologia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/enzimologiaRESUMO
N,N'-Disubstituted ketene aminals are good bioisosteres of thiourea functional groups. We report the design and synthesis of a novel class of ketene aminal-based lactam derivatives as potent and orally active FXa inhibitors.