RESUMEN
A class of imidazoisoindole (III) heme-binding indoleamine-2,3-dioxygenase (IDO1) inhibitors were optimized via structure-based drug design into a series of tryptophan-2,3-dioxygenase (TDO)-selective inhibitors. Kynurenine pathway modulation was demonstrated in vivo, which enabled evaluation of TDO as a potential cancer immunotherapy target. As means of mitigating the risk of drug-drug interactions arising from cytochrome P450 inhibition, a novel property-based drug design parameter, herein referred to as the CYP Index, was implemented for the design of inhibitors with appreciable selectivity for TDO over CYP3A4. We anticipate the CYP Index will be a valuable design parameter for optimizing CYP inhibition of any small molecule inhibitor containing a Lewis basic motif capable of binding heme.
RESUMEN
Disruption of interleukin-13 (IL-13) signaling with large molecule antibody therapies has shown promise in diseases of allergic inflammation. Given that IL-13 recruits several members of the Janus Kinase family (JAK1, JAK2, and TYK2) to its receptor complex, JAK inhibition may offer an alternate small molecule approach to disrupting IL-13 signaling. Herein we demonstrate that JAK1 is likely the isoform most important to IL-13 signaling. Structure-based design was then used to improve the JAK1 potency of a series of previously reported JAK2 inhibitors. The ability to impede IL-13 signaling was thereby significantly improved, with the best compounds exhibiting single digit nM IC50's in cell-based assays dependent upon IL-13 signaling. Appropriate substitution was further found to influence inhibition of a key off-target, LRRK2. Finally, the most potent compounds were found to be metabolically labile, which makes them ideal scaffolds for further development as topical agents for IL-13 mediated diseases of the lungs and skin (for example asthma and atopic dermatitis, respectively).
Asunto(s)
Dermatitis Atópica/genética , Interleucina-13/metabolismo , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Humanos , Transducción de SeñalRESUMEN
Tryptophan 2,3-dioxygenase 2 (TDO2) catalyzes the conversion of tryptophan to the immunosuppressive metabolite kynurenine. TDO2 overexpression has been observed in a number of cancers; therefore, TDO inhibition may be a useful therapeutic intervention for cancers. We identified an aminoisoxazole series as potent TDO2 inhibitors from a high-throughput screen (HTS). An extensive medicinal chemistry effort revealed that both the amino group and the isoxazole moiety are important for TDO2 inhibitory activity. Computational modeling yielded a binding hypothesis and provided insight into the observed structure-activity relationships. The optimized compound 21 is a potent TDO2 inhibitor with modest selectivity over indolamine 2,3-dioxygenase 1 (IDO1) and with improved human whole blood stability.
RESUMEN
The identification of a novel fused triazolo-pyrrolopyridine scaffold, optimized derivatives of which display nanomolar inhibition of Janus kinase 1, is described. Prototypical example 3 demonstrated lower cell potency shift, better permeability in cells and higher oral exposure in rat than the corresponding, previously reported, imidazo-pyrrolopyridine analogue 2. Examples 6, 7 and 18 were subsequently identified from an optimization campaign and demonstrated modest selectivity over JAK2, moderate to good oral bioavailability in rat with overall pharmacokinetic profiles comparable to that reported for an approved pan-JAK inhibitor (tofacitinib).
Asunto(s)
Janus Quinasa 1/antagonistas & inhibidores , Piridinas/farmacología , Animales , Cristalografía por Rayos X , Janus Quinasa 1/química , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/química , Cinética , Modelos Moleculares , Piridinas/química , Pirroles/química , Pirroles/farmacología , RatasRESUMEN
Herein we report on the structure-based discovery of a C-2 hydroxyethyl moiety which provided consistently high levels of selectivity for JAK1 over JAK2 to the imidazopyrrolopyridine series of JAK1 inhibitors. X-ray structures of a C-2 hydroxyethyl analogue in complex with both JAK1 and JAK2 revealed differential ligand/protein interactions between the two isoforms and offered an explanation for the observed selectivity. Analysis of historical data from related molecules was used to develop a set of physicochemical compound design parameters to impart desirable properties such as acceptable membrane permeability, potent whole blood activity, and a high degree of metabolic stability. This work culminated in the identification of a highly JAK1 selective compound (31) exhibiting favorable oral bioavailability across a range of preclinical species and robust efficacy in a rat CIA model.
Asunto(s)
Antirreumáticos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Imidazoles/síntesis química , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Piridinas/síntesis química , Pirroles/síntesis química , Administración Oral , Animales , Antirreumáticos/química , Antirreumáticos/farmacología , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/etiología , Disponibilidad Biológica , Permeabilidad de la Membrana Celular , Colágeno , Cristalografía por Rayos X , Perros , Haplorrinos , Compuestos Heterocíclicos con 3 Anillos/química , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Imidazoles/química , Imidazoles/farmacología , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Janus Quinasa 1/química , Janus Quinasa 2/química , Células de Riñón Canino Madin Darby , Microsomas Hepáticos/metabolismo , Modelos Moleculares , Estructura Molecular , Piridinas/química , Piridinas/farmacología , Pirroles/química , Pirroles/farmacología , Ratas , EstereoisomerismoRESUMEN
Herein we describe our successful efforts in obtaining C-2 substituted imidazo-pyrrolopyridines with improved JAK1 selectivity relative to JAK2 by targeting an amino acid residue that differs between the two isoforms (JAK1: E966; JAK2: D939). Efforts to improve cellular potency by reducing the polarity of the inhibitors are also detailed. The X-ray crystal structure of a representative inhibitor in complex with the JAK1 enzyme is also disclosed.
Asunto(s)
Descubrimiento de Drogas , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Pirroles/farmacología , Animales , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Humanos , Imidazoles/química , Janus Quinasa 1/metabolismo , Janus Quinasa 2/metabolismo , Masculino , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , Piridinas/administración & dosificación , Piridinas/química , Pirroles/administración & dosificación , Pirroles/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
Herein we report the discovery of the C-2 methyl substituted imidazopyrrolopyridine series and its optimization to provide potent and orally bioavailable JAK1 inhibitors with selectivity over JAK2. The C-2 methyl substituted inhibitor 4 exhibited not only improved JAK1 potency relative to unsubstituted compound 3 but also notable JAK1 vs JAK2 selectivity (20-fold and >33-fold in biochemical and cell-based assays, respectively). Features of the X-ray structures of 4 in complex with both JAK1 and JAK2 are delineated. Efforts to improve the in vitro and in vivo ADME properties of 4 while maintaining JAK1 selectivity are described, culminating in the discovery of a highly optimized and balanced inhibitor (20). Details of the biological characterization of 20 are disclosed including JAK1 vs JAK2 selectivity levels, preclinical in vivo PK profiles, performance in an in vivo JAK1-mediated PK/PD model, and attributes of an X-ray structure in complex with JAK1.
Asunto(s)
Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Compuestos Heterocíclicos con 3 Anillos/química , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Animales , Bioensayo , Disponibilidad Biológica , Línea Celular , Cristalografía por Rayos X , Perros , Hepatocitos/citología , Compuestos Heterocíclicos con 3 Anillos/farmacocinética , Humanos , Janus Quinasa 1/química , Janus Quinasa 2/química , Ratones , Modelos Moleculares , Ratas , Relación Estructura-ActividadRESUMEN
A therapeutic rationale is proposed for the treatment of inflammatory diseases, such as rheumatoid arthritis (RA), by specific targeting of the JAK1 pathway. Examination of the preferred binding conformation of clinically effective, pan-JAK inhibitor 1 led to identification of a novel, tricyclic hinge binding scaffold 3. Exploration of SAR through a series of cycloamino and cycloalkylamino analogues demonstrated this template to be highly tolerant of substitution, with a predisposition to moderate selectivity for the JAK1 isoform over JAK2. This study culminated in the identification of subnanomolar JAK1 inhibitors such as 22 and 49, having excellent cell potency, good rat pharmacokinetic characteristics, and excellent kinase selectivity. Determination of the binding modes of the series in JAK1 and JAK2 by X-ray crystallography supported the design of analogues to enhance affinity and selectivity.
Asunto(s)
Imidazoles/química , Janus Quinasa 1/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/química , Piridinas/farmacología , Animales , Línea Celular , Janus Quinasa 1/química , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/química , Modelos Moleculares , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Estructura Terciaria de Proteína , Piridinas/síntesis química , Piridinas/farmacocinética , Ratas , Especificidad por SustratoAsunto(s)
Antirreumáticos/farmacología , Diseño de Fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Agammaglobulinemia Tirosina Quinasa , Secuencia de Aminoácidos , Animales , Antirreumáticos/química , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/enzimología , Sitios de Unión , Modelos Animales de Enfermedad , Datos de Secuencia Molecular , Oligopéptidos/química , Oligopéptidos/metabolismo , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/metabolismo , Roedores , Relación Estructura-ActividadRESUMEN
The synthesis of novel [1,2,4]oxadiazoles and their structure-activity relationship (SAR) for the inhibition of tryptase and related serine proteases is presented. Elaboration of the P'-side afforded potent, selective, and orally bioavailable tryptase inhibitors.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Serina Endopeptidasas/efectos de los fármacos , Administración Oral , Disponibilidad Biológica , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Modelos Moleculares , Relación Estructura-Actividad , TriptasasRESUMEN
Beginning with the peptide sequence Cbz-Ile-Glu(OtBu)-Ala-Leu found in PSI (3), a series of vinyl sulfones (VS) were synthesized for evaluation as inhibitors of the chymotrypsin-like activity of the 20S proteasome. Variations at the key P3 position confirmed the importance of a long side chain capped with a hydrophobic group for optimal potency, consistent with a model of binding to the S3 subsite. The tert-butyl glutamic ester initially used at P3 gave plasma unstable, insoluble compounds and was replaced with the better isostere, N-beta-neopentyl asparagine. The inhibitors were shortened by replacing the N-terminal Cbz-isoleucine with a p-tosyl group without loss of potency. Small l-amino acids were used at P2, where d-substitution was not tolerated. The resulting optimized P4-P3-P2 sequence was grafted onto a novel proteasome inhibitor warhead, 2-keto-1,3,4-oxadiazoles (KOD), to produce reversible, subnanomolar proteasome inhibitors that were 1000-fold selective versus cathepsin B (CatB), cathepsin S (CatS), and trypsin-like as well as PGPH-like proteasome activity. A number of compounds in both the VS and the KOD series exhibited growth inhibitory effects against the human prostate cancer cell line PC3 at submicromolar concentrations.
Asunto(s)
Oligopéptidos/síntesis química , Oxadiazoles/síntesis química , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma , Sulfonas/síntesis química , Compuestos de Vinilo/síntesis química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Bovinos , Proliferación Celular/efectos de los fármacos , Estabilidad de Medicamentos , Humanos , Técnicas In Vitro , Modelos Moleculares , Oligopéptidos/química , Oligopéptidos/farmacología , Oxadiazoles/química , Oxadiazoles/farmacología , Complejo de la Endopetidasa Proteasomal/química , Subunidades de Proteína/antagonistas & inhibidores , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Solubilidad , Relación Estructura-Actividad , Sulfonas/química , Sulfonas/farmacología , Compuestos de Vinilo/química , Compuestos de Vinilo/farmacologíaRESUMEN
Using a scaleable, directed library approach based on orthogonally protected advanced intermediates, we have prepared a series of potent keto-1,2,4-oxadiazoles designed to explore the P(2) binding pocket of human mast cell tryptase, while building in a high degree of selectivity over human trypsin and other serine proteases.
Asunto(s)
Inhibidores Enzimáticos/síntesis química , Mastocitos/efectos de los fármacos , Oxadiazoles/síntesis química , Serina Endopeptidasas/efectos de los fármacos , Animales , Sitios de Unión/efectos de los fármacos , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Haplorrinos , Humanos , Mastocitos/enzimología , Ratones , Estructura Molecular , Oxadiazoles/química , Oxadiazoles/farmacología , Estereoisomerismo , Relación Estructura-Actividad , TriptasasRESUMEN
We have prepared a series of achiral aminoacetonitriles, bearing tri-ring benzamide moieties and an aminocyclohexanecarboxylate residue at P2. This combination of binding elements resulted in sub-250 pM, reversible, selective, and orally bioavailable cathepsin K inhibitors. Lead compounds displayed single digit nanomolar inhibition in vitro (of rabbit osteoclast-mediated degradation of bovine bone). The best compound in this series, 39n (CRA-013783/L-006235), was orally bioavailable in rats, with a terminal half-life of over 3 h. 39n was dosed orally in ovariectomized rhesus monkeys once per day for 7 days. Collagen breakdown products were reduced by up to 76% dose-dependently. Plasma concentrations of 39n above the bone resorption IC50 after 24 h indicated a correlation between functional cellular and in vivo assays. Inhibition of collagen breakdown by cathepsin K inhibitors suggests this mechanism of action may be useful in osteoporosis and other indications involving bone resorption.
Asunto(s)
Benzamidas/síntesis química , Conservadores de la Densidad Ósea/síntesis química , Catepsinas/antagonistas & inhibidores , Nitrilos/síntesis química , Tiazoles/síntesis química , Administración Oral , Animales , Benzamidas/química , Benzamidas/farmacología , Disponibilidad Biológica , Biomarcadores/orina , Conservadores de la Densidad Ósea/química , Conservadores de la Densidad Ósea/farmacología , Resorción Ósea/orina , Catepsina K , Catepsinas/química , Bovinos , Colágeno/antagonistas & inhibidores , Colágeno/metabolismo , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Cinética , Macaca mulatta , Modelos Moleculares , Estructura Molecular , Nitrilos/química , Nitrilos/farmacología , Conejos , Ratas , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacologíaRESUMEN
Adenosine is an endogenous neuromodulator that when produced in the central and the peripheral nervous systems has anticonvulsant, anti-inflammatory, and analgesic properties. However, efforts to use adenosine receptor agonists are plagued by dose-limiting cardiovascular side effects. As an alternative, we explored the use of adenosine kinase inhibitors (AKIs) as potential antiseizure agents and demonstrated an adenosine receptor mediated therapeutic effect in the absence of overt cardiovascular side effects. These activities were associated with elevation of extracellular adenosine concentrations due to inhibition of AK in a site and event specific manner. Several tubercidin based AKIs, including the ribo- and lyxo-furanosyltubercidin analogues as well as the newly discovered erythro-furanosyltubercidin analogues, designed to prevent 5'-O-phosphorylation and associated toxicities, were tested for their analgesic activity in the rat formalin paw model. Described herein are the synthesis, enzyme inhibition structure-activity relationships (SARs) of erythro-furanosyltubercidin analogues, and SARs of analgesic activity of various classes of AKIs. Also reported is the characterization of a lead AKI, 19d (GP3966), an orally bioavailable compound (F% = 60% in dog) which exhibits broad-spectrum analgesic activities (ED50 < or = 4 mg/kg, per os) that are reversible with an adenosine receptor antagonist (theophylline).
Asunto(s)
Adenosina Quinasa/antagonistas & inhibidores , Adenosina/análogos & derivados , Analgésicos/síntesis química , Tubercidina/análogos & derivados , Tubercidina/síntesis química , Adenosina/efectos adversos , Adenosina/síntesis química , Adenosina/farmacología , Administración Oral , Analgésicos/efectos adversos , Analgésicos/farmacología , Animales , Área Bajo la Curva , Disponibilidad Biológica , Callithrix , Perros , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Relación Estructura-Actividad , Tubercidina/efectos adversos , Tubercidina/farmacologíaRESUMEN
A novel series of nonpeptidic biaryl compounds was identified as potent and reversible inhibitors of cathepsin K. The P2-P3 amide bond of a known amino acetonitrile dipeptide 1 was replaced with a phenyl ring, thereby giving rise to this biaryl series that retained potency vs cathepsin K and showed an improved selectivity profile against other cathepsins. Structural modification within this series resulted in the identification of compound (R)-2, a potent human cathepsin K inhibitor (IC(50) = 3 nM) that is selective versus cathepsins B (IC(50) = 3950 nM), L (IC(50) = 3725 nM), and S (IC(50) = 2010 nM). In an in vitro assay involving rabbit osteoclasts and bovine bone, compound (R)-2 inhibited bone resorption with an IC(50) of 95 nM. It was shown that, unlike some peptidic nitrile inhibitors of cysteine proteases, the nitrile moiety of (R)-2 is not converted to the corresponding amide 3 by cathepsin K. This indicates that this class of nonpeptidic nitrile inhibitors is unlikely to be hydrolyzed by cysteine proteases. Furthermore, the inhibition of cathepsin K by compound (R)-2 was shown to be fully reversible and not observably time-dependent. To demonstrate the efficacy of compound (R)-2 in vivo, it was administered to ovariectomized (OVX) rhesus monkeys at 20 mg/kg, po once daily for 8 days, and a urinary marker of bone turnover, N-telopeptide of type I collagen (uNTx), was measured. During the eight-day dosing period, the mean reduction by compound (R)-2 in uNTx was 80% (p < 0.001). This demonstrates that inhibition of cathepsin K leads to an inhibition of this bone resorption marker in OVX rhesus monkeys and strongly suggests that inhibition of cathepsin K is a viable therapeutic approach for the treatment of osteoporosis.
Asunto(s)
Compuestos de Bifenilo/síntesis química , Catepsinas/antagonistas & inhibidores , Nitrilos/síntesis química , Piperazinas/síntesis química , Inhibidores de Proteasas/síntesis química , Animales , Biomarcadores/orina , Compuestos de Bifenilo/farmacocinética , Compuestos de Bifenilo/farmacología , Resorción Ósea/metabolismo , Huesos/efectos de los fármacos , Huesos/patología , Catepsina B/antagonistas & inhibidores , Catepsina B/química , Catepsina K , Catepsina L , Catepsinas/química , Bovinos , Colágeno/orina , Colágeno Tipo I , Cisteína Endopeptidasas , Humanos , Técnicas In Vitro , Macaca mulatta , Nitrilos/química , Nitrilos/farmacocinética , Nitrilos/farmacología , Osteoclastos/efectos de los fármacos , Osteoclastos/patología , Ovariectomía , Péptidos/orina , Piperazinas/farmacocinética , Piperazinas/farmacología , Inhibidores de Proteasas/farmacocinética , Inhibidores de Proteasas/farmacología , Conejos , Estereoisomerismo , Relación Estructura-Actividad , Factores de TiempoRESUMEN
Cathepsin K is highly expressed in human osteoclasts, and is implicated in bone resorption. This makes it an attractive target for the treatment of osteoporosis. Peptides containing 2-amino-1'-hydroxymethyl ketones and 2-amino-1'-alkoxymethyl ketones were discovered as potent inhibitors of cathepsin K. A novel synthetic route was devised to facilitate rapid elucidation of the SAR of these inhibitors. The synthesis and SAR of hydroxymethyl ketones are presented.