RESUMO
The discovery and some of the basic structure-activity relationships of a series of novel nonpeptide inhibitors of blood coagulation Factor Xa is described. These inhibitors are functionalized beta-alanines, exemplified by 2a. Docking experiments placing 2a in the active site of Factor Xa implied that the most expeditious route to enhancing in vitro potency was to modify the group occupying the S3 site of the enzyme. Increasing the hydrophobic contacts between the inhibitor and the enzyme in this region led to 8, which has served as the prototype for this series. In addition, an enantioselective synthesis of these substituted beta-alanines was also developed.
Assuntos
Inibidores do Fator Xa , beta-Alanina/análogos & derivados , beta-Alanina/síntese química , Animais , Sítios de Ligação , Bovinos , Desenho de Fármacos , Fator Xa/química , Humanos , Ligação de Hidrogênio , Indicadores e Reagentes , Recém-Nascido , Modelos Moleculares , Conformação Molecular , Conformação Proteica , Relação Estrutura-Atividade , Trombina/antagonistas & inibidores , Inibidores da Tripsina/síntese química , Inibidores da Tripsina/química , Inibidores da Tripsina/farmacologia , beta-Alanina/química , beta-Alanina/farmacologiaRESUMO
A series of structural analogs of the Pseudomonas aeruginosa autoinducer [PAI, N-3-oxo-dodecanoyl homoserine lactone] were obtained and tested for their ability to act as autoinducers in stimulating the expression of the gene for elastase (lasB) by measuring beta-galactosidase production from a lasB-lacZ gene fusion in the presence of the transcriptional activator LasR. The data suggest that the length of the acyl side chain of the autoinducer molecule is the most critical factor for activity. Replacement of the ring O by S in the homoserine lactone moiety can be tolerated. Tritium-labelled PAI ([3H]PAI) was synthesized and used to demonstrate the association of [3H]PAI with cells overexpressing LasR. The PAI analogs were also tested for their ability to compete with [3H]PAI for binding of LasR. Results from the competition assays suggest that once again the length of the acyl side chain appears to be crucial for antagonist activity. The presence of the 3-oxo moiety also plays a significant role in binding since analogs which lacked this moiety were much less effective in blocking binding of [3H]PAI. All analogs demonstrating competition with PAI in binding to LasR also exhibited the ability to activate lasB expression, suggesting that they are functional analogs of PAI.
Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Homosserina/análogos & derivados , Lactonas/química , Pseudomonas aeruginosa/fisiologia , Ligação Competitiva , Proteínas de Ligação a DNA/metabolismo , Homosserina/química , Homosserina/metabolismo , Lactonas/metabolismo , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Relação Estrutura-Atividade , Transativadores/metabolismoRESUMO
We report on formation of bilateral renal calculi secondary to sulfasalazine therapy for juvenile rheumatoid arthritis. The condition was successfully treated with extracorporeal shock wave lithotripsy. Analysis of the fragments with thin layer chromatography and nuclear magnetic resonance revealed acetylsulfapyridine, a metabolite of sulfasalazine.
