RESUMEN
The nuclear receptor retinoic acid receptor-related orphan receptor gamma t (RORγt) is a transcription factor that drives Th17 cell differentiation and IL-17 production in both innate and adaptive immune cells. The IL-23/IL-17 pathway is implicated in major autoimmune and inflammatory diseases. RORγt lies at the core of this pathway and represents an attractive opportunity for intervention with small molecule therapeutics. Despite diverse chemical series having been reported, combining high potency and nuclear receptor selectivity with good physicochemical properties remains a challenging endeavor in the field of RORγt drug discovery. We recently described the discovery and evaluation of a new class of potent and selective RORγt inverse agonists based on a thiazole scaffold. Herein we describe the successful optimization of this class by incorporation of an additional amide moiety at the 4-position of the thiazole core. In several optimization cycles, we have reduced human PXR activation, improved solubility, and increased potency while maintaining nuclear receptor selectivity. X-ray crystallographic analysis of compound 1g bound in the sterol binding site of the ligand binding domain of RORγt was largely consistent with an earlier structure, guiding further insight into the molecular mechanism for RORγt inhibition with this series. Compound 1g is orally bioavailable, potent in a human whole blood assay and proved to be efficacious in an ex-vivo IL-17A assay, and was selected for preclinical evaluation.
Asunto(s)
Amidas/química , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Bibliotecas de Moléculas Pequeñas/química , Tiazoles/química , Enfermedades Autoinmunes/tratamiento farmacológico , Sitios de Unión , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Humanos , Inflamación/tratamiento farmacológico , Interleucina-17/química , Modelos Moleculares , Estructura Molecular , Unión Proteica , Bibliotecas de Moléculas Pequeñas/farmacología , Relación Estructura-Actividad , Tiazoles/farmacologíaRESUMEN
Starting from previously identified thiazole-2-carboxamides exemplified by compound 1/6, two new series of RORγt inverse agonists with significantly improved aqueous solubility, ADME parameters and oral PK properties were discovered. These scaffolds were identified from a bioisosteric amide replacement approach. Amongst the variety of heterocycles explored, a 1,3,4-oxadiazole led to compounds with the best overall profile for SAR development and in vivo exploration. In an ex vivo mouse PD model, concentration dependent efficacy was demonstrated and compounds 3/5 and 6/3 were profiled in a 5-day rat tolerability study.
Asunto(s)
Amidas/farmacología , Descubrimiento de Drogas , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Oxadiazoles/farmacología , Tiazoles/farmacología , Administración Oral , Amidas/administración & dosificación , Amidas/química , Animales , Relación Dosis-Respuesta a Droga , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Estructura Molecular , Oxadiazoles/administración & dosificación , Oxadiazoles/química , Ratas , Relación Estructura-Actividad , Tiazoles/administración & dosificación , Tiazoles/químicaRESUMEN
We have previously reported the syntheses of a series of 3,6-disubstituted quinolines as modulators of the retinoic acid receptor-related orphan receptor gamma t (RORγt). These molecules are potent binders but are high molecular weight and they exhibited poor solubility at pH 2 and pH 7. This manuscript details our efforts at improving physical chemical properties for this series of compounds by increasing the diversity at the 3-position (i.e. introducing heteroatoms and lowering the molecular weight). These efforts have led to molecules which are potent binders with improved solubility.
Asunto(s)
Agonismo Inverso de Drogas , Quinolinas/agonistas , Animales , Humanos , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Aberrant activation of matrix metalloproteinases (MMPs) is a common feature of pathological cascades observed in diverse disorders, such as cancer, fibrosis, immune dysregulation, and neurodegenerative diseases. MMP-9, in particular, is highly dynamically regulated in several pathological processes. Development of MMP inhibitors has therefore been an attractive strategy for therapeutic intervention. However, a long history of failed clinical trials has demonstrated that broad-spectrum MMP inhibitors have limited clinical utility, which has spurred the development of inhibitors selective for individual MMPs. Attaining selectivity has been technically challenging because of sequence and structural conservation across the various MMPs. Here, through a biochemical and structural screening paradigm, we have identified JNJ0966, a highly selective compound that inhibited activation of MMP-9 zymogen and subsequent generation of catalytically active enzyme. JNJ0966 had no effect on MMP-1, MMP-2, MMP-3, MMP-9, or MMP-14 catalytic activity and did not inhibit activation of the highly related MMP-2 zymogen. The molecular basis for this activity was characterized as an interaction of JNJ0966 with a structural pocket in proximity to the MMP-9 zymogen cleavage site near Arg-106, which is distinct from the catalytic domain. JNJ0966 was efficacious in reducing disease severity in a mouse experimental autoimmune encephalomyelitis model, demonstrating the viability of this therapeutic approach. This discovery reveals an unprecedented pharmacological approach to MMP inhibition, providing an opportunity to improve selectivity of future clinical drug candidates. Targeting zymogen activation in this manner may also allow for pharmaceutical exploration of other enzymes previously viewed as intractable drug targets.
Asunto(s)
Precursores Enzimáticos/antagonistas & inhibidores , Precursores Enzimáticos/química , Metaloproteinasa 9 de la Matriz/química , Inhibidores de la Metaloproteinasa de la Matriz/química , Regulación Alostérica , Animales , Células COS , Dominio Catalítico , Chlorocebus aethiops , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Humanos , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Dominios ProteicosRESUMEN
The nuclear receptor retinoic acid receptor-related orphan receptor gamma t (RORγt) is a transcription factor that drives Th17 cell differentiation and IL-17 production in both innate and adaptive immune cells. The IL-23/IL-17 pathway is implicated in major autoimmune and inflammatory diseases. RORγt lies at the core of this pathway and represents an attractive opportunity for intervention with a small molecule. Despite diverse chemical series having been reported, combining high potency and nuclear receptor selectivity with good physicochemical properties remains a challenging endeavor in the field of RORγt drug discovery. We describe the discovery and evaluation of a new class of potent and selective RORγt inverse agonists based on a thiazole core. Acid analog 1j demonstrated oral bioavailability in rats and was potent in a human whole blood assay, suggesting potential utility in treating autoimmune and inflammatory diseases such as psoriasis. X-ray crystallographic data helped to elucidate the molecular mechanism for RORγt inhibition with this series.
Asunto(s)
Receptores de Ácido Retinoico/agonistas , Tiazoles/farmacología , Animales , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Estructura Molecular , Ratas , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/químicaRESUMEN
A high-throughput screen of the ligand binding domain of the nuclear receptor retinoic acid-related orphan receptor gamma t (RORγt) employing a thermal shift assay yielded a quinoline tertiary alcohol hit. Optimization of the 2-, 3- and 4-positions of the quinoline core using structure-activity relationships and structure-based drug design methods led to the discovery of a series of modulators with improved RORγt inhibitory potency and inverse agonism properties.
Asunto(s)
Diseño de Fármacos , Agonismo Inverso de Drogas , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/antagonistas & inhibidores , Quinolinas/química , Quinolinas/farmacología , Humanos , Simulación del Acoplamiento Molecular , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Relación Estructura-Actividad , Células Th17/efectos de los fármacosRESUMEN
We identified 6-substituted quinolines as modulators of the retinoic acid receptor-related orphan receptor gamma t (RORγt). The synthesis of this class of RORγt modulators is reported, and optimization of the substituents at the quinoline 6-position that produced compounds with high affinity for the receptor is detailed. This effort identified molecules that act as potent, full inverse agonists in a RORγt-driven cell-based reporter assay. The X-ray crystal structures of two full inverse agonists from this chemical series bound to the RORγt ligand binding domain are disclosed, and we highlight the interaction of a hydrogen-bond acceptor on the 6-position substituent of the inverse agonist with Glu379:NH as a conserved binding contact.
Asunto(s)
Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Quinolinas/farmacología , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Humanos , Ligandos , Modelos Moleculares , Estructura Molecular , Quinolinas/síntesis química , Quinolinas/química , Relación Estructura-ActividadRESUMEN
A novel series of benzyl substituted thieno[2,3-d]pyrimidines were identified as potent A2A receptor antagonists. Several five- and six-membered heterocyclic replacements for the optimized methylfuran were explored. Select compounds effectively reverse catalepsy in mice when dosed orally.
Asunto(s)
Antagonistas del Receptor de Adenosina A2/química , Pirimidinas/química , Receptor de Adenosina A2A/metabolismo , Antagonistas del Receptor de Adenosina A2/farmacocinética , Antagonistas del Receptor de Adenosina A2/uso terapéutico , Animales , Encéfalo/metabolismo , Catalepsia/tratamiento farmacológico , Semivida , Humanos , Cinética , Ratones , Unión Proteica , Pirimidinas/farmacocinética , Pirimidinas/uso terapéutico , Ratas , Receptor de Adenosina A2A/químicaRESUMEN
Complement C1s protease inhibitors have potential utility in the treatment of diseases associated with activation of the classical complement pathway such as humorally mediated graft rejection, ischemia-reperfusion injury (IRI), vascular leak syndrome, and acute respiratory distress syndrome (ARDS). The utility of biphenylsulfonyl-thiophene-carboxamidine small-molecule C1s inhibitors are limited by their poor in vivo pharmacokinetic properties. Pegylation of a potent analog has provided compounds with good potency and good in vivo pharmacokinetic properties.
Asunto(s)
Amidas/química , Complemento C1s/antagonistas & inhibidores , Diseño de Fármacos , Polietilenglicoles/química , Inhibidores de Proteasas/síntesis química , Tiofenos/química , Animales , Complemento C1s/metabolismo , Semivida , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacocinética , RatasRESUMEN
Bruton's tyrosine kinase (BTK) is a cytoplasmic tyrosine kinase that plays a critical role in the activation of B cells, macrophages, and osteoclasts. Given the key role of these cell types in the pathology of autoimmune disorders, BTK inhibitors have the potential to improve treatment outcomes in multiple diseases. Herein, we report the discovery and characterization of a novel potent and selective covalent 4-oxo-4,5-dihydro-3H-1-thia-3,5,8-triazaacenaphthylene-2-carboxamide BTK inhibitor chemotype. Compound 27 irreversibly inhibits BTK by targeting a noncatalytic cysteine residue (Cys481) for covalent bond formation. Compound 27 is characterized by selectivity for BTK, potent in vivo BTK occupancy that is sustained after it is cleared from systemic circulation, and dose-dependent efficacy at reducing joint inflammation in a rat collagen-induced arthritis model.
RESUMEN
Two reactive metabolites were identified in vivo for the dual A(2A)/A(1) receptor antagonist 1. Two strategies were implemented to successfully mitigate the metabolic liabilities associated with 1. Optimization of the arylindenopyrimidines led to a number of amide, ether, and amino analogs having comparable in vitro and in vivo activity.
Asunto(s)
Antagonistas del Receptor de Adenosina A1 , Antagonistas del Receptor de Adenosina A2 , Neurotransmisores/química , Pirimidinas/química , Animales , Catalepsia/tratamiento farmacológico , Modelos Animales de Enfermedad , Ratones , Neurotransmisores/síntesis química , Neurotransmisores/uso terapéutico , Pirimidinas/síntesis química , Pirimidinas/uso terapéutico , Receptor de Adenosina A1/metabolismo , Receptor de Adenosina A2A/metabolismo , Relación Estructura-ActividadRESUMEN
To identify Janus kinase (JAK) inhibitors that selectively target gastrointestinal tissues with limited systemic exposures, a class of imidazopyrrolopyridines with a range of physical properties was prepared and evaluated. We identified compounds with low intrinsic permeability and determined a correlation between permeability and physicochemical properties, clogP and tPSA, for a subset of compounds. This low intrinsic permeability translated into compounds displaying high colonic exposure and low systemic exposure after oral dosing at 25 mg/kg in mouse. In a mouse PK/PD model, oral dosing of lead compound 2 demonstrated dose-dependent inhibition of pSTAT phosphorylation in colonic explants post-oral dose but low systemic exposure and no measurable systemic pharmacodynamic activity. We thus demonstrate the utility of JAK inhibitors with low intrinsic permeability as a feasible approach to develop gut-restricted, pharmacologically active molecules with a potential advantage over systemically available compounds that are limited by systemic on-target adverse events.
Asunto(s)
Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Inhibidores de las Cinasas Janus/farmacología , Inhibidores de las Cinasas Janus/farmacocinética , Piridinas/farmacología , Piridinas/farmacocinética , Administración Oral , Animales , Perros , Descubrimiento de Drogas , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/metabolismo , Inhibidores de las Cinasas Janus/administración & dosificación , Inhibidores de las Cinasas Janus/química , Quinasas Janus/antagonistas & inhibidores , Quinasas Janus/metabolismo , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos C57BL , Permeabilidad , Fosforilación/efectos de los fármacos , Piridinas/administración & dosificación , Piridinas/químicaRESUMEN
Complement activation has been implicated in disease states such as hereditary angioedema, ischemia-reperfusion injury, acute respiratory distress syndrome, and acute transplant rejection. Even though the complement cascade provides several protein targets for potential therapeutic intervention only two complement inhibitors have been approved so far for clinical use including anti-C5 antibodies for the treatment of paroxysmal nocturnal hemoglobinuria and purified C1-esterase inhibitor replacement therapy for the control of hereditary angioedema flares. In the present study, optimization of potency and physicochemical properties of a series of thiophene amidine-based C1s inhibitors with potential utility as intravenous agents for the inhibition of the classical pathway of complement is described.
Asunto(s)
Complemento C1s/antagonistas & inhibidores , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Animales , Sitios de Unión , Semivida , Modelos Moleculares , Estructura Molecular , Ratas , Relación Estructura-ActividadRESUMEN
The activity and stability of the p53 tumor suppressor are regulated by the human homologue of the mouse double minute 2 (Hdm2) oncoprotein. It has been hypothesized that small molecules disrupting the Hdm2:p53 complex would allow for the activation of p53 and result in growth suppression. We have identified small-molecule inhibitors of the Hdm2:p53 interaction using our proprietary ThermoFluor microcalorimetry technology. Medicinal chemistry and structure-based drug design led to the development of an optimized series of benzodiazepinediones, including TDP521252 and TDP665759. Activities were dependent on the expression of wild-type (wt) p53 and Hdm2 as determined by lack of potency in mutant or null p53-expressing cell lines or cells engineered to no longer express Hdm2 and wt p53. TDP521252 and TDP665759 inhibited the proliferation of wt p53-expressing cell lines with average IC(50)s of 14 and 0.7 micromol/L, respectively. These results correlated with the direct cellular dissociation of Hdm2 from wt p53 observed within 15 minutes in JAR choriocarcinoma cells. Additional activities of these inhibitors in vitro include stabilization of p53 protein levels, up-regulation of p53 target genes in a DNA damage-independent manner, and induction of apoptosis in HepG2 cells. Administration of TDP665759 to mice led to an increase in p21(waf1/cip1) levels in liver samples. Finally, TDP665759 synergizes with doxorubicin both in culture and in an A375 xenograft model to decrease tumor growth. Taken together, these data support the potential utility of small-molecule inhibitors of the Hdm2:p53 interaction for the treatment of wt p53-expressing tumors.
Asunto(s)
Benzodiazepinonas/farmacología , Doxorrubicina/farmacología , Proteínas Proto-Oncogénicas c-mdm2/efectos de los fármacos , Proteína p53 Supresora de Tumor/efectos de los fármacos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Benzodiazepinas/química , Benzodiazepinas/farmacología , Benzodiazepinonas/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Femenino , Humanos , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/metabolismo , Ratones , Ratones Desnudos , Complejos Multiproteicos , Mutación , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The binding of lead compounds and drugs to human serum albumin (HSA) is a ubiquitous problem in drug discovery since it modulates the availability of the leads and drugs to their intended target, which is linked to biological efficacy. In our continuing efforts to identify small molecule alpha(V)beta(3) and alpha(V)beta(5) dual antagonists, we recently reported indoles 2-4 as potent and selective alpha(V)beta(3)/alpha(V)beta(5) antagonists with good oral bioavailability profile. In spite of subnanomolar binding affinity of these compounds to human alpha(V)beta(3) and alpha(V)beta(5) integrins, high HSA binding (96.5-97.3%) emerged as a limiting feature for these leads. Structure-activity HSA binding data of organic acids reported in the literature have demonstrated that the incorporation of polar groups into a given molecule can dramatically decrease the affinity toward HSA. We sought to apply this strategy by examining the effects of such modifications in both the central core constrain and the substituent beta to the carboxylate. Most of these derivatives were prepared in good yields through a cesium fluoride-catalyzed coupling reaction. This reaction was successful with a variety of nitrogen-containing scaffolds (20, 33, and 43) and selected acetylenic derivatives (16, 19, and 34). Among the compounds synthesized, the 3-[5-[2-(5,6,7,8-tetrahydro [1,8]naphthyridin-2-yl)ethoxy]indol-1-yl]-3-[5-(N,N-dimethylaminomethyl)-3-pyridyl]propionic acid (25) was found to be the most promising derivative within this novel series with a subnanomolar affinity for both alpha(v)beta(3) and alpha(v)beta(5) (IC(50) = 0.29 and 0.16 nM, respectively), similar to our initial lead receptor antagonists 2-4, and exhibiting a low HSA protein binding (40% bound, K(d) = 1.1+/-0.4 x 10(3) microM) and an improved in vitro stability profile toward human and mouse microsomes (99.9% and 98.7% remaining after 10 min). Moreover, the selectivity of 25 toward alpha(5)beta(1) and IIbIIIa integrins was perfectly maintained when compared to the parent leads 2-4. Thus, compound 25 was selected as a new lead with improved drug-like properties for further evaluations in the field of oncology and osteoporosis.
Asunto(s)
Integrina alfaVbeta3/antagonistas & inhibidores , Integrinas/antagonistas & inhibidores , Receptores de Vitronectina/antagonistas & inhibidores , Albúmina Sérica/metabolismo , Alquinos/síntesis química , Alquinos/química , Bencimidazoles/química , Esterificación , Humanos , Hipoxantinas/síntesis química , Hipoxantinas/química , Indoles/síntesis química , Indoles/química , Estructura Molecular , Propionatos/síntesis química , Propionatos/química , Unión Proteica , Relación Estructura-ActividadRESUMEN
The IL-23/IL-17 pathway is implicated in autoimmune diseases, particularly psoriasis, where biologics targeting IL-23 and IL-17 have shown significant clinical efficacy. Retinoid-related orphan nuclear receptor gamma t (RORγt) is required for Th17 differentiation and IL-17 production in adaptive and innate immune cells. We identified JNJ-54271074, a potent and highly-selective RORγt inverse agonist, which dose-dependently inhibited RORγt-driven transcription, decreased co-activator binding and promoted interaction with co-repressor protein. This compound selectively blocked Th17 differentiation, significantly reduced IL-17A production from memory T cells, and decreased IL-17A- and IL-22-producing human and murine γδ and NKT cells. In a murine collagen-induced arthritis model, JNJ-54271074 dose-dependently suppressed joint inflammation. Furthermore, JNJ-54271074 suppressed IL-17A production in human PBMC from rheumatoid arthritis patients. RORγt-deficient mice showed decreased IL-23-induced psoriasis-like skin inflammation and cytokine gene expression, consistent with dose-dependent inhibition in wild-type mice through oral dosing of JNJ-54271074. In a translational model of human psoriatic epidermal cells and skin-homing T cells, JNJ-54271074 selectively inhibited streptococcus extract-induced IL-17A and IL-17F. JNJ-54271074 is thus a potent, selective RORγt modulator with therapeutic potential in IL-23/IL-17 mediated autoimmune diseases.
Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Péptidos Cíclicos/administración & dosificación , Psoriasis/tratamiento farmacológico , Células Th17/efectos de los fármacos , Administración Oral , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-17/metabolismo , Interleucinas/metabolismo , Ratones , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Péptidos Cíclicos/farmacología , Psoriasis/genética , Psoriasis/metabolismo , Células Th17/citología , Células Th17/metabolismo , Transcripción Genética , Interleucina-22RESUMEN
A novel series of potent and selective alpha(v)beta(3)/alpha(v)beta(5) dual( )()inhibitors was designed, synthesized, and evaluated against several integrins. These compounds were synthesized through a Mitsunobu reaction between the guanidinium mimetics and the corresponding central templates. Guanidinium mimetics with enhaced rigidity (i.e., (2-pyridylamino)propoxy versus the 2-(6-methylamino-2-pyridyl)ethoxy) led to improved activity toward alpha(v)beta(3). Exemplary oral bioavailability in mice was achieved using the indole central scaffold. Although, oral bioavailability was maintained when the indole molecular core was replace with the bioisosteric benzofuran or benzothiophene ring systems, it was found to not significantly impact the integrin activity or selectivity. However, the indole series displayed the best in vivo pharmacokinetic properties. Thus, the indole series was selected for further structure-activity relationships to obtain more potent alpha(v)beta(3)/alpha(v)beta(5) dual antagonist with improved oral bioavailability.
Asunto(s)
Benzoxazoles/síntesis química , Indoles/síntesis química , Integrina alfaVbeta3/antagonistas & inhibidores , Integrinas/antagonistas & inhibidores , Receptores de Vitronectina/antagonistas & inhibidores , Tiofenos/síntesis química , Administración Oral , Animales , Benzoxazoles/química , Benzoxazoles/farmacología , Disponibilidad Biológica , Células CACO-2 , Diseño de Fármacos , Humanos , Indoles/química , Indoles/farmacología , Ratones , Permeabilidad , Relación Estructura-Actividad , Tiofenos/química , Tiofenos/farmacologíaRESUMEN
Development of alphavbeta3-integrin inhibitors has been hampered by a lack of pharmacodynamic endpoints to identify doses that inhibit alphavbeta3 in vivo. To address this need, we developed an alphavbeta3 radioreceptor assay (RRA) that could be performed in 100% plasma. The RRA was based on 125I-echistatin binding to plate-immobilized alphavbeta3. Small molecule alphavbeta3 inhibitors efficiently competed echistatin binding to alphavbeta3 when the assay was carried out in buffer. However, when carried out in 100% plasma, the RRA revealed a 45 to >3000-fold loss in compound potencies. The losses in potency reflected, in part, the high plasma protein binding by the compounds examined. The RRA was adapted as an ex vivo pharmacodynamic model. Echistatin binding was measured in the presence of plasma harvested at timed intervals from rats dosed with select compounds. Using this pharmacodynamic model, compound and dose selection was optimized for further testing in models of corneal angiogenesis. Moderate anti-angiogenic activity was achieved when rats were dosed sufficient to achieve sustained (>50%) plasma inhibition through the trough interval. Thus, the RRA provided a simple technique to rank order compound potency in plasma, and could find general use as an ex vivo pharmacodynamic assay to select compounds and doses for preclinical and clinical proof-of-principle studies.
Asunto(s)
Integrina alfaVbeta3/antagonistas & inhibidores , Integrina alfaVbeta3/sangre , Ensayo de Unión Radioligante/métodos , Inhibidores de la Angiogénesis/farmacocinética , Inhibidores de la Angiogénesis/farmacología , Animales , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Proteínas Sanguíneas/metabolismo , Córnea/irrigación sanguínea , Córnea/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intercelular , Masculino , Neovascularización Patológica/prevención & control , Péptidos/sangre , Péptidos/farmacocinética , Unión Proteica , Ratas , Ratas Sprague-DawleyRESUMEN
A stereocontrolled route to the deschloro cyclopentyl core of the palau'amines and styloguanidines has been developed. This strategy makes use of the intramolecular Pauson-Khand cyclization of an enyne with a "transient N-O tether" to construct a five-membered carbocycle in a diastereoselective fashion. [reaction: see text]
RESUMEN
The design and characterization of two, dual adenosine A(2A)/A(1) receptor antagonists in several animal models of Parkinson's disease is described. Compound 1 was previously reported as a potential treatment for Parkinson's disease. Further characterization of 1 revealed that it was metabolized to reactive intermediates that caused the genotoxicity of 1 in the Ames and mouse lymphoma L51784 assays. The identification of the metabolites enabled the preparation of two optimized compounds 13 and 14 that were devoid of the metabolic liabilities associated with 1. Compounds 13 and 14 are potent dual A(2A)/A(1) receptor antagonists that have excellent activity, after oral administration, across a number of animal models of Parkinson's disease including mouse and rat models of haloperidol-induced catalepsy, mouse and rat models of reserpine-induced akinesia, and the rat 6-hydroxydopamine (6-OHDA) lesion model of drug-induced rotation.