RESUMEN
The discovery of lead compound 2e was described. Its covalent binding to HCV NS5B polymerase enzyme was investigated by X-ray analysis. The results of distribution, metabolism and pharmacokinetics were reported. Compound 2e was demonstrated to be potent (replicon GT-1b EC50 = 0.003 µM), highly selective, and safe in in vitro and in vivo assays.
Asunto(s)
Inhibidores Enzimáticos/química , Hepacivirus/enzimología , Indoles/química , Quinolinas/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Animales , Cristalografía por Rayos X , Perros , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Haplorrinos , Humanos , Indoles/síntesis química , Indoles/farmacocinética , Indoles/farmacología , Masculino , Simulación de Dinámica Molecular , Unión Proteica , Estructura Terciaria de Proteína , Quinolinas/síntesis química , Quinolinas/farmacocinética , Quinolinas/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas no Estructurales Virales/metabolismoRESUMEN
Starting with the indole-based C-3 pyridone lead HCV polymerase inhibitor 2, extensive SAR studies were performed at different positions of the indole core. The best C-5 groups were found to be compact and nonpolar moieties and that the C-6 attachments were not affecting potency. Limited N-1 benzyl-type substituent studies indicated that the best substitutions were fluoro or methyl groups at 2' or 5' positions of the benzyl group. To improve pharmacokinetic (PK) properties, acylsulfonamides were incorporated as acid isosteres at the C-2 position. Further optimization of the combination at N-1, C-2, C-5, and C-6 resulted in the identification of compound 56, which had an excellent potency in both NS5B enzyme (IC(50) = 0.008 µM) and cell-based replicon (EC(50) = 0.02 µM) assays and a good oral PK profile with area-under-the curve (AUC) of 14 and 8 µM·h in rats and dogs, respectively. X-ray structure of inhibitor 56 bound to the enzyme was also reported.
Asunto(s)
Antivirales/síntesis química , Hepacivirus/enzimología , Indoles/síntesis química , Sulfonamidas/síntesis química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Administración Oral , Animales , Antivirales/farmacocinética , Antivirales/farmacología , Células CACO-2 , Cristalografía por Rayos X , Perros , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Humanos , Indoles/química , Indoles/farmacocinética , Indoles/farmacología , Modelos Moleculares , Estructura Molecular , Permeabilidad , Ratas , Replicón , Relación Estructura-Actividad , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologíaRESUMEN
Development of SAR at the C2 position of indole lead 1, a palm site inhibitor of HCV NS5B polymerase (NS5B IC(50)=0.053µM, replicon EC(50)=4.8µM), is described. Initial screening identified an acyl sulfonamide moiety as an isostere for the C2 carboxylic acid group. Further SAR investigation resulted in identification of acyl sufonamide analog 7q (NS5B IC(50)=0.039µM, replicon EC(50)=0.011µM) with >100-fold improved replicon activity.
Asunto(s)
Antivirales/farmacología , Indoles/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Química Farmacéutica/métodos , Cristalografía por Rayos X/métodos , Diseño de Fármacos , Humanos , Enlace de Hidrógeno , Concentración 50 Inhibidora , Modelos Químicos , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad , Sulfonamidas/químicaRESUMEN
SAR development of indole-based palm site inhibitors of HCV NS5B polymerase exemplified by initial indole lead 1 (NS5B IC(50)=0.9 µM, replicon EC(50)>100 µM) is described. Structure-based drug design led to the incorporation of novel heterocyclic moieties at the indole C3-position which formed a bidentate interaction with the protein backbone. SAR development resulted in leads 7q (NS5B IC(50)=0.032 µM, replicon EC(50)=1.4 µM) and 7r (NS5B IC(50)=0.017 µM, replicon EC(50)=0.3 µM) with improved enzyme and replicon activity.
Asunto(s)
Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Compuestos Heterocíclicos/farmacología , Indoles/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Ácidos Carboxílicos , Dominio Catalítico/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Indoles/síntesis química , Indoles/química , Modelos Moleculares , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad , Proteínas no Estructurales Virales/metabolismoRESUMEN
HCV infection affects more than 170 million people worldwide and many of those patients will reach the end stage complications of the disease which include hepatocarcinoma and liver failure. The success rate for treatment of patients infected with genotype-1 is about 40%. Therefore, novel treatments are needed to combat the infection. The HCV NS3 protease inhibitor Boceprevir (1) was reported by our research group and efforts continue for the discovery of more potent compounds with improved pharmacokinetic profiles. A new series of HCV NS3 protease inhibitors having a cyclic sulfone P3-cap have been discovered. Compounds 43 and 44 showed K(i)* values in the single-digit nM range and their cellular potency was improved by 10-fold compared to 1. The pharmacokinetic profiles of 43 and 44 in rats and monkeys were also improved to achieve higher plasma levels after oral administration.
Asunto(s)
Hepacivirus/enzimología , Oligopéptidos/síntesis química , Inhibidores de Serina Proteinasa/síntesis química , Sulfonas/síntesis química , Administración Oral , Animales , Cristalografía por Rayos X , Haplorrinos , Modelos Moleculares , Oligopéptidos/farmacocinética , Oligopéptidos/farmacología , Ratas , Inhibidores de Serina Proteinasa/farmacocinética , Inhibidores de Serina Proteinasa/farmacología , Estereoisomerismo , Relación Estructura-Actividad , Sulfonas/farmacocinética , Sulfonas/farmacologíaRESUMEN
In the search for a second generation HCV protease inhibitor, molecular modeling studies of the X-ray crystal structure of Boceprevir1 bound to the NS3 protein suggest that expansion into the S4 pocket could provide additional hydrophobic Van der Waals interactions. Effective replacement of the P4 tert-butyl with a cyclohexylmethyl ligand led to inhibitor 2 with improved enzyme and replicon activities. Subsequent modeling and SAR studies led to the pyridine 38 and sulfone analogues 52 and 53 with vastly improved PK parameters in monkeys, forming a new foundation for further exploration.
Asunto(s)
Antivirales/química , Prolina/análogos & derivados , Inhibidores de Proteasas/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Animales , Antivirales/farmacocinética , Antivirales/farmacología , Área Bajo la Curva , Disponibilidad Biológica , Cristalografía por Rayos X , Haplorrinos , Modelos Moleculares , Prolina/química , Prolina/farmacocinética , Prolina/farmacología , Inhibidores de Proteasas/farmacocinética , Inhibidores de Proteasas/farmacología , Ratas , Relación Estructura-ActividadRESUMEN
A highly efficient and practical route to 3,4-isopropylidene proline I, starting from (+)-3-carene, was developed. The three continuous stereocenters were constructed using the inherent chirality of the starting natural product 2. The overall yield for the 12-step synthesis is 34%. The optimized sequence leading to 1 has been successfully applied on a multigram scale, thereby establishing the practicality of this route.
Asunto(s)
Compuestos Alílicos/síntesis química , Monoterpenos/química , Prolina/análogos & derivados , Prolina/síntesis química , Compuestos Alílicos/química , Monoterpenos Bicíclicos , Catálisis , Cromatografía en Gel , Ciclización , Datos de Secuencia Molecular , Estructura Molecular , Prolina/química , EstereoisomerismoRESUMEN
SAR studies on the extension of P3 unit of Boceprevir (1, SCH 503034) with amides and lactams and their synthesis is described. Extensive SAR studies resulted in the identification of 36 bearing 4, 4-dimethyl lactam as the new P4 cap unit with improved potency (K(i)( *)=15nM, EC 90=70nM) and pharmacokinetic properties (Rat AUC (PO)=3.52microMh) compared to 1.
Asunto(s)
Amidas/química , Antivirales/química , Lactamas/química , Oligopéptidos/química , Inhibidores de Proteasas/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Amidas/síntesis química , Amidas/farmacocinética , Animales , Antivirales/síntesis química , Antivirales/farmacocinética , Sitios de Unión , Cristalografía por Rayos X , Lactamas/síntesis química , Lactamas/farmacocinética , Oligopéptidos/síntesis química , Oligopéptidos/farmacocinética , Prolina/análogos & derivados , Prolina/química , Prolina/farmacocinética , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/farmacocinética , Ratas , Relación Estructura-Actividad , Proteínas no Estructurales Virales/metabolismoRESUMEN
Boceprevir (SCH 503034), 1, a novel HCV NS3 serine protease inhibitor discovered in our laboratories, is currently undergoing phase III clinical trials. Detailed investigations toward a second generation protease inhibitor culminated in the discovery of narlaprevir (SCH 900518), 37, with improved potency (â¼10-fold over 1), pharmacokinetic profile and physicochemical characteristics, currently in phase II human trials. Exploration of synthetic sequence for preparation of 37 resulted in a route that required no silica gel purification for the entire synthesis.
RESUMEN
Hepatitis C virus (HCV) infection is a global health crisis leading to liver cirrhosis, hepatocellular carcinoma, and liver failure in humans. Recently, we disclosed the discovery of Boceprevir, SCH 503034 (1), a novel, potent, selective, orally bioavailable NS3 protease inhibitor that is currently undergoing phase III clinical trials. Our efforts toward a second generation HCV NS3 serine protease inhibitor were directed at improving the overall profile of the inhibitor. This article will elaborate on our studies leading to the discovery of new P4 modified inhibitors with enhanced potency and improved oral bioavailability. Thus, introduction of ether and carbamate-derived P4 moieties resulted in improving the replicon potency significantly. Incorporation of the P' secondary amide residue afforded significant improvement in pharmacokinetic properties. Combining the preferred moieties, identified from comprehensive SAR studies, resulted in inhibitors that displayed superior potency and very good oral as well as target organ exposure in rats.
Asunto(s)
Descubrimiento de Drogas , Hepacivirus/enzimología , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/farmacocinética , Proteínas no Estructurales Virales/antagonistas & inhibidores , Amidas/química , Animales , Modelos Moleculares , Conformación Molecular , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/química , Ratas , Relación Estructura-ActividadRESUMEN
HCV infection is considered a silent epidemic because most people infected do not develop acute symptoms. Instead, the disease progresses to a chronic state leading to cirrhosis and hepatocarcinoma. Novel therapies are needed to combat this major health threat. The HCV NS3 serine protease has been the target of continuous investigation because of its pivotal role in viral replication. Herein, we present the P1-P3 macrocyclization approach followed for identification of HCV NS3 inhibitors as potential backup candidates to our first generation drug candidate, Sch 503034 (1). Different P1-P3 linkers were investigated to identify novel macrocyclic scaffolds. SAR exploration of P3-caps in the macrocyclic cores allowed the identification of l-serine derived macrocycle 32 (Ki* = 3 nM, EC90 = 30 nM) and allo-threonine derived macrocycle 36 (Ki* = 3 nM, EC90 = 30 nM) as potent HCV NS3 protease inhibitors.
Asunto(s)
Compuestos Macrocíclicos/síntesis química , Inhibidores de Serina Proteinasa/síntesis química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Antivirales/síntesis química , Antivirales/farmacología , Diseño de Fármacos , Compuestos Macrocíclicos/farmacología , Inhibidores de Serina Proteinasa/farmacologíaRESUMEN
[reaction: see text] A highly stereoselective synthesis of beta-amino sulfones and sulfonamides via addition of sulfonyl anions to chiral N-sulfinyl imines is described. The addition reaction proceeds in good yield (75-99%) and stereoselectivity.
RESUMEN
An asymmetric aldol reaction between aldehyde 31 and imide 32, followed at a later stage by ring-closing metathesis (38 --> 40), are key reactions used to make optically pure allylic alcohol 40. Radical cyclization of the derived Stork bromo acetals gives lactol ethers 43, which were degraded to generate a quaternary center carrying a methoxycarboxyl group (44 --> 47). Compound 47 was converted into (+)-puraquinonic acid; and comparison with a natural sample established that the configuration of the natural compound is 2R (1).
Asunto(s)
Indenos/síntesis química , Antineoplásicos/síntesis química , Antineoplásicos/química , Diferenciación Celular , Ciclización , Humanos , Indenos/química , EstereoisomerismoRESUMEN
Silane 15, easily constructed by simple methods, undergoes a cascade of radical reactions when treated with a stannane to afford the bicyclic 1,2-oxasiloles 16, with the major isomer having the ester group anti to the O-Si unit. This isomer was elaborated via 19 into 6, a deoxy derivative of the Corey lactone. In a related sequence, ketone 24 was converted into silane 35; this, too, underwent the radical cascade to afford the highly substituted 1,2-oxasiloles 36. Again the major isomer had the ester and O-Si units in an anti relationship. Elaboration of 36 (major isomer) gave the Corey lactone derivative 7. A key intermediate (32) in this second sequence was also prepared in optically pure form by starting with 2-deoxy-D-ribose. Compound 19 was converted into 8, a sequence that constitutes a formal synthesis of methyl (+/-)-epi-jasmonate. Two examples were found of selective silylation of a propargylic secondary hydroxyl in the presence of an ordinary secondary hydroxyl.