RESUMEN
Optimization of a pyrrolidine-based template using structure-based design and physicochemical considerations has provided a development candidate 20b (3082) with submicromolar potency in the HCV replicon and good pharmacokinetic properties.
Asunto(s)
Antivirales/síntesis química , Hepacivirus/efectos de los fármacos , Pirrolidinas/síntesis química , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Animales , Antivirales/química , Antivirales/farmacología , Sitios de Unión , Disponibilidad Biológica , Chlorocebus aethiops , Hepacivirus/enzimología , Modelos Moleculares , Pirrolidinas/química , Pirrolidinas/farmacología , ARN Polimerasa Dependiente del ARN/química , Ratas , Estereoisomerismo , Relación Estructura-Actividad , Células VeroRESUMEN
A series of chiral, (S)-proline-alpha-methylpyrrolidine-5,5-trans-lactam serine protease inhibitors has been developed as antivirals of human cytomegalovirus (HCMV). The SAR of the functionality on the proline nitrogen has shown that derivatives of para-substituted phenyl ureas > para-substituted phenyl sulfonamides > para-substituted phenyl carboxamide for activity against HCMV deltaAla protease, producing para-substituted phenyl ureas with single figure nM potency (K(i)) against the viral enzyme. The SAR of the functionality on the lactam nitrogen has defined the steric and electronic requirements for high human plasma stability while retaining good activity against HCMV protease. The combination of high potency against HCMV deltaAla protease and high human plasma stability has produced compounds with significant in vitro antiviral activity against human cytomegalovirus with the 6-hydroxymethyl benzothiazole derivative 72 being equivalent in potency to ganciclovir. The parent benzothiazole 56 had good pharmacokinetics in dogs with 29% bioavailability and good brain and ocular penetration in guinea pigs.
Asunto(s)
Antivirales/síntesis química , Antivirales/farmacología , Citomegalovirus/efectos de los fármacos , Citomegalovirus/enzimología , Lactamas/síntesis química , Lactamas/farmacología , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/farmacología , Pirroles/síntesis química , Pirroles/farmacología , Serina Endopeptidasas/metabolismo , Animales , Antivirales/sangre , Disponibilidad Biológica , Encéfalo/metabolismo , Células Cultivadas , Perros , Diseño de Fármacos , Ensayo de Inmunoadsorción Enzimática , Ojo/metabolismo , Ganciclovir/farmacología , Cobayas , Semivida , Humanos , Indicadores y Reactivos , Cinética , Espectrometría de Masas , Modelos Moleculares , Inhibidores de Proteasas/sangre , Relación Estructura-Actividad , Especificidad por SustratoRESUMEN
[reaction: see text] In this, the first of two Letters, we describe how a P3/P4 urea linking unit was used to greatly enhance the biochemical and replicon potency of inhibitors based upon the pyrrolidine-5,5-trans-lactam template. Compound 7b demonstrated a 100 nM IC(50) in the replicon cell-based surrogate HCV assay.
Asunto(s)
Antivirales/síntesis química , Hepacivirus/enzimología , Lactamas/química , Inhibidores de Proteasas/síntesis química , Pirrolidinas/química , Urea/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Antivirales/química , Antivirales/farmacología , Cristalografía por Rayos X , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Concentración 50 Inhibidora , Conformación Molecular , Estructura Molecular , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacosRESUMEN
The SAR development is described for a series of N-acyl pyrrolidine inhibitors of the Hepatitis C virus RNA-dependent RNA polymerase, NS5B, from tractable Delta21 enzyme inhibitors to an example with antiviral activity in a cellular assay (HCV replicon).
Asunto(s)
Antivirales/farmacología , Química Farmacéutica/métodos , Hepacivirus/química , Hepacivirus/genética , Pirrolidinas/antagonistas & inhibidores , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Replicón/genética , Proteínas no Estructurales Virales/farmacología , Antivirales/química , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Concentración 50 Inhibidora , Modelos Químicos , Conformación Molecular , ARN Viral/química , Proteínas no Estructurales Virales/química , Replicación Viral/efectos de los fármacosRESUMEN
A recombinant vaccinia virus, expressing the NS3-to-NS5 region of the N clone of hepatitis C virus (HCV), was generated and utilized both in a gel-based assay and in an enzyme-linked immunosorbent assay (ELISA) to evaluate the pyrrolidine-5,5-trans-lactams, a series of inhibitors of the HCV NS3/4A protease. The absolute levels of processed, mature HCV nonstructural proteins in this system were found to decrease in the presence of the trans-lactams. Monitoring of this reduction enabled end points and 50% inhibitory concentrations to be calculated in order to rank the active compounds according to potency. These compounds had no effect on the transcription or translation of the NS3-5 polyprotein at concentrations shown to inhibit NS3/4A protease, and they were shown to be specific inhibitors of this protease. The ELISA, originally developed using the vaccinia virus expression system, was modified to utilize Huh-7 cells containing an HCV replicon. Results with this assay correlated well with those obtained with the recombinant vaccinia virus assays. These results demonstrate the utility of these assays for the characterization of NS3/4A protease inhibitors. In addition, inhibitors of other viral targets, such as polymerase and helicase, can be evaluated in the context of the replicon ELISA.