RESUMEN
The structure-based design, chemical synthesis, and biological evaluation of peptide-derived human rhinovirus (HRV) 3C protease (3CP) inhibitors are described. These compounds incorporate various Michael acceptor moieties and are shown to irreversibly bind to HRV serotype 14 3CP with inhibition activities (kobs/[I]) ranging from 100 to 600 000 M-1 s-1. These inhibitors are also shown to exhibit antiviral activity when tested against HRV-14-infected H1-HeLa cells with EC50's approaching 0.50 microM. Extensive structure-activity relationships developed by Michael acceptor alteration are reported along with the evaluation of several compounds against HRV serotypes other than 14. A 2.0 A crystal structure of a peptide-derived inhibitor complexed with HRV-2 3CP is also detailed.
Asunto(s)
Antivirales , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa , Diseño de Fármacos , Oligopéptidos , Rhinovirus/efectos de los fármacos , Proteínas Virales , Proteasas Virales 3C , Animales , Antivirales/síntesis química , Antivirales/química , Antivirales/metabolismo , Antivirales/farmacología , Sitios de Unión , Línea Celular Transformada , Cristalografía por Rayos X , Cisteína Endopeptidasas/química , Inhibidores de Cisteína Proteinasa/síntesis química , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/metabolismo , Inhibidores de Cisteína Proteinasa/farmacología , Estabilidad de Medicamentos , Células HeLa , Humanos , Oligopéptidos/síntesis química , Oligopéptidos/química , Oligopéptidos/metabolismo , Oligopéptidos/farmacología , Conformación Proteica , Ratas , Ratas Sprague-Dawley , Rhinovirus/enzimología , Relación Estructura-ActividadRESUMEN
The structure-based design, chemical synthesis, and biological evaluation of various human rhinovirus (HRV) 3C protease (3CP) inhibitors which incorporate P1 lactam moieties in lieu of an L-glutamine residue are described. These compounds are comprised of a tripeptidyl or peptidomimetic binding determinant and an ethyl propenoate Michael acceptor moiety which forms an irreversible covalent adduct with the active site cysteine residue of the 3C enzyme. The P1-lactam-containing inhibitors display significantly increased 3CP inhibition activity along with improved antirhinoviral properties relative to corresponding L-glutamine-derived molecules. In addition, several lactam-containing compounds exhibit excellent selectivity for HRV 3CP over several other serine and cysteine proteases and are not appreciably degraded by a variety of biological agents. One of the most potent inhibitors (AG7088, mean antirhinoviral EC90 approximately 0.10 microM, n = 46 serotypes) is shown to warrant additional preclinical development to explore its potential for use as an antirhinoviral agent.
Asunto(s)
Antivirales/síntesis química , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/síntesis química , Glutamina/química , Isoxazoles/síntesis química , Lactamas/síntesis química , Oligopéptidos/síntesis química , Pirrolidinonas/síntesis química , Rhinovirus/enzimología , Proteínas Virales , Proteasas Virales 3C , Antivirales/química , Antivirales/farmacología , Línea Celular , Cristalografía por Rayos X , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/farmacología , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Isoxazoles/química , Isoxazoles/farmacología , Lactamas/química , Lactamas/farmacología , Modelos Moleculares , Imitación Molecular , Oligopéptidos/química , Oligopéptidos/farmacología , Fenilalanina/análogos & derivados , Pirrolidinonas/química , Pirrolidinonas/farmacología , Rhinovirus/efectos de los fármacos , Relación Estructura-Actividad , Valina/análogos & derivadosRESUMEN
Azelastine, an antihistamine with additional pharmacologic properties, was evaluated for a possible influence on pharmacokinetic and electrocardiographic parameters due to its coadministration with CYP3A4 inhibitor ketoconazole (200 mg every 12 hrs). Twelve volunteers entered this three-period, open-label study. Electrocardiographic parameters (PR, QRS and QTc intervals and U-wave morphology) were monitored after 14 days of azelastine HCl (4.4 mg every 12 hrs), after 7 days of either azelastine/ketoconazole or azelastine/placebo, and after a 21-day washout period, which was then followed by a 7-day administration of ketoconazole alone. None of the treatments resulted in meaningful alterations of electrocardiographic variables. Pharmacokinetic parameters could not be estimated because ketoconazole metabolites interfered with azelastine assay procedures. In vitro tests with human liver microsomes were used to characterize azelastine's inhibition spectrum. Azelastine did not inhibit CYP3A4 activity but it did inhibit CYP2D6 and CYP2C19 activity with Ki values exceeding maximum plasma concentration by 120 to 800-fold. Therefore, in vitro tests and the absence of electrocardiographic effects suggests azelastine can be safely administered with CYP3A4 inhibitors.
Asunto(s)
Antifúngicos/farmacología , Electrocardiografía/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Antagonistas de los Receptores Histamínicos H1/farmacología , Cetoconazol/farmacología , Ftalazinas/farmacología , Adulto , Antifúngicos/metabolismo , Antifúngicos/farmacocinética , Área Bajo la Curva , Sistema Enzimático del Citocromo P-450/metabolismo , Método Doble Ciego , Antagonistas de los Receptores Histamínicos H1/metabolismo , Antagonistas de los Receptores Histamínicos H1/farmacocinética , Humanos , Cetoconazol/metabolismo , Cetoconazol/farmacocinética , Masculino , Ftalazinas/metabolismo , Ftalazinas/farmacocinéticaRESUMEN
Novel tripeptidyl C-terminal Michael acceptors with an ester replacement of the P(2)-P(3) amide bond were investigated as irreversible inhibitors of the human rhinovirus (HRV) 3C protease (3CP). When screened against HRV serotype-14 the best compound was shown to have very good 3CP inhibition (k(obs)/[I]=270,000M(-1)s(-1)) and potent in vitro antiviral activity (EC(50)=7.0nM).