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1.
Science ; 361(6408): 1234-1238, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30072577

RESUMO

Phosphorothioate nucleotides have emerged as powerful pharmacological substitutes of their native phosphodiester analogs with important translational applications in antisense oligonucleotide (ASO) therapeutics and cyclic dinucleotide (CDN) synthesis. Stereocontrolled installation of this chiral motif has long been hampered by the systemic use of phosphorus(III) [P(III)]-based reagent systems as the sole practical means of oligonucleotide assembly. A fundamentally different approach is described herein: the invention of a P(V)-based reagent platform for programmable, traceless, diastereoselective phosphorus-sulfur incorporation. The power of this reagent system is demonstrated through the robust and stereocontrolled synthesis of various nucleotidic architectures, including ASOs and CDNs, via an efficient, inexpensive, and operationally simple protocol.


Assuntos
Nucleotídeos/química , Oligonucleotídeos Fosforotioatos/síntese química , Terapia Genética , Isomerismo , Oligonucleotídeos Fosforotioatos/química , Oligonucleotídeos Fosforotioatos/uso terapêutico , Enxofre/química
2.
ACS Med Chem Lett ; 9(5): 472-477, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29795762

RESUMO

There is a significant unmet medical need for more efficacious and rapidly acting antidepressants. Toward this end, negative allosteric modulators of the N-methyl-d-aspartate receptor subtype GluN2B have demonstrated encouraging therapeutic potential. We report herein the discovery and preclinical profile of a water-soluble intravenous prodrug BMS-986163 (6) and its active parent molecule BMS-986169 (5), which demonstrated high binding affinity for the GluN2B allosteric site (Ki = 4.0 nM) and selective inhibition of GluN2B receptor function (IC50 = 24 nM) in cells. The conversion of prodrug 6 to parent 5 was rapid in vitro and in vivo across preclinical species. After intravenous administration, compounds 5 and 6 have exhibited robust levels of ex vivo GluN2B target engagement in rodents and antidepressant-like activity in mice. No significant off-target activity was observed for 5, 6, or the major circulating metabolites met-1 and met-2. The prodrug BMS-986163 (6) has demonstrated an acceptable safety and toxicology profile and was selected as a preclinical candidate for further evaluation in major depressive disorder.

4.
J Pharmacol Exp Ther ; 363(3): 377-393, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28954811

RESUMO

(R)-3-((3S,4S)-3-fluoro-4-(4-hydroxyphenyl)piperidin-1-yl)-1-(4-methylbenzyl)pyrrolidin-2-one (BMS-986169) and the phosphate prodrug 4-((3S,4S)-3-fluoro-1-((R)-1-(4-methylbenzyl)-2-oxopyrrolidin-3-yl)piperidin-4-yl)phenyl dihydrogen phosphate (BMS-986163) were identified from a drug discovery effort focused on the development of novel, intravenous glutamate N-methyl-d-aspartate 2B receptor (GluN2B) negative allosteric modulators (NAMs) for treatment-resistant depression (TRD). BMS-986169 showed high binding affinity for the GluN2B subunit allosteric modulatory site (Ki = 4.03-6.3 nM) and selectively inhibited GluN2B receptor function in Xenopus oocytes expressing human N-methyl-d-aspartate receptor subtypes (IC50 = 24.1 nM). BMS-986169 weakly inhibited human ether-a-go-go-related gene channel activity (IC50 = 28.4 µM) and had negligible activity in an assay panel containing 40 additional pharmacological targets. Intravenous administration of BMS-986169 or BMS-986163 dose-dependently increased GluN2B receptor occupancy and inhibited in vivo [3H](+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine ([3H]MK-801) binding, confirming target engagement and effective cleavage of the prodrug. BMS-986169 reduced immobility in the mouse forced swim test, an effect similar to intravenous ketamine treatment. Decreased novelty suppressed feeding latency, and increased ex vivo hippocampal long-term potentiation was also seen 24 hours after acute BMS-986163 or BMS-986169 administration. BMS-986169 did not produce ketamine-like hyperlocomotion or abnormal behaviors in mice or cynomolgus monkeys but did produce a transient working memory impairment in monkeys that was closely related to plasma exposure. Finally, BMS-986163 produced robust changes in the quantitative electroencephalogram power band distribution, a translational measure that can be used to assess pharmacodynamic activity in healthy humans. Due to the poor aqueous solubility of BMS-986169, BMS-986163 was selected as the lead GluN2B NAM candidate for further evaluation as a novel intravenous agent for TRD.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Organofosfatos/uso terapêutico , Piperidinas/uso terapêutico , Pró-Fármacos/uso terapêutico , Pirrolidinonas/uso terapêutico , Receptores de N-Metil-D-Aspartato/metabolismo , Administração Intravenosa , Regulação Alostérica , Animais , Antidepressivos/efeitos adversos , Antidepressivos/farmacocinética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Ondas Encefálicas/efeitos dos fármacos , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Transtornos Dissociativos/induzido quimicamente , Macaca fascicularis , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Organofosfatos/efeitos adversos , Organofosfatos/farmacocinética , Piperidinas/efeitos adversos , Piperidinas/farmacocinética , Pró-Fármacos/efeitos adversos , Pró-Fármacos/farmacocinética , Pirrolidinonas/efeitos adversos , Pirrolidinonas/farmacocinética , Ensaio Radioligante , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Xenopus
5.
Eur J Pharmacol ; 812: 104-112, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28690193

RESUMO

Alzheimer's disease is associated with the accumulation of amyloid-ß (Aß) in the brain. In particular, the 42-amino acid form, Aß1-42, is thought to play a key role in the disease. It is therefore of interest that diverse compounds, known as γ-secretase modulators (GSM), can selectively decrease Aß1-42 production without inhibiting the production of other forms of Aß. Here we describe the novel discovery of synergistic inhibition of Aß by certain combinations of GSMs. Cell cultures were treated with pairwise combinations of GSMs to determine how Aß peptide production was affected. Analysis of isobolograms and calculation of the combination index showed that BMS-869780 and GSM-2 were highly synergistic. Additional combinations of GSMs revealed that inhibition of Aß occurred only when one GSM was of the "acid GSM" structural class and the other was of the "non-acid GSM" class. A total of 15 representative acid/non-acid GSM combinations were shown to inhibit Aß production, whereas 10 pairwise combinations containing two acid GSMs or containing two non-acid GSMs did not inhibit Aß. We also discovered that lasalocid, a natural product, is a potent GSM. Lasalocid is unique in that it did not synergize with other GSMs. Synergism did not translate in vivo perhaps because of biochemical differences between the cell culture model and brain. These findings reinforce the pharmacological differences between different structural classes of GSMs, and may help to exploit the potential of γ-secretase as a drug target.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/biossíntese , Fragmentos de Peptídeos/biossíntese , Inibidores de Proteases/farmacologia , Acetatos/farmacologia , Animais , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Camundongos , Piperidinas/farmacologia
6.
Eur J Pharmacol ; 807: 1-11, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28438647

RESUMO

The α7 nicotinic acetylcholine receptor is thought to play an important role in human cognition. Here we describe the in vivo effects of BMS-902483, a selective potent α7 nicotinic acetylcholine receptor partial agonist, in relationship to α7 nicotinic acetylcholine receptor occupancy. BMS-902483 has low nanomolar affinity for rat and human α7 nicotinic acetylcholine receptors and elicits currents in cells expressing human or rat α7 nicotinic acetylcholine receptors that are about 60% of the maximal acetylcholine response. BMS-902483 improved 24h novel object recognition memory in mice with a minimal effective dose (MED) of 0.1mg/kg and reversed MK-801-induced deficits in a rat attentional set-shifting model of executive function with an MED of 3mg/kg. Enhancement of novel object recognition was blocked by the silent α7 nicotinic acetylcholine receptor agonist, NS6740, demonstrating that activity of BMS-902483 was mediated by α7 nicotinic acetylcholine receptors. BMS-902483 also reversed ketamine-induced deficits in auditory gating in rats, and enhanced ex vivo hippocampal long-term potentiation examined 24h after dosing in mice. Results from an ex vivo brain homogenate binding assay showed that α7 receptor occupancy ranged from 64% (novel object recognition) to ~90% (set shift and gating) at the MED for behavioral and sensory processing effects of BMS-902483.


Assuntos
Cognição/efeitos dos fármacos , Agonismo Parcial de Drogas , Agonistas Nicotínicos/farmacologia , Quinuclidinas/farmacologia , Filtro Sensorial/efeitos dos fármacos , Compostos de Espiro/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Atenção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Humanos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos , Ratos
7.
ACS Med Chem Lett ; 8(3): 366-371, 2017 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-28337332

RESUMO

The therapeutic treatment of negative symptoms and cognitive dysfunction associated with schizophrenia is a significant unmet medical need. Preclinical literature indicates that α7 neuronal nicotinic acetylcholine (nACh) receptor agonists may provide an effective approach to treating cognitive dysfunction in schizophrenia. We report herein the discovery and evaluation of 1c (BMS-933043), a novel and potent α7 nACh receptor partial agonist with high selectivity against other nicotinic acetylcholine receptor subtypes (>100-fold) and the 5-HT3A receptor (>300-fold). In vivo activity was demonstrated in a preclinical model of cognitive impairment, mouse novel object recognition. BMS-933043 has completed Phase I clinical trials.

8.
Bioorg Med Chem Lett ; 27(5): 1261-1266, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28169167

RESUMO

Quinuclidine-containing spirooxazolines, as described in the previous report in this series, were demonstrated to have utility as α7 nicotinic acetylcholine receptor (α7 nAChR) partial agonists. In this work, the SAR of this chemotype was expanded to include an array of diazine heterocyclic substitutions. Many of the heterocyclic analogs were potent partial agonists of the α7 receptor, selective against other nicotinic receptors and the serotinergic 5HT3A receptor. (1'S,3'R,4'S)-N-(6-phenylpyrimidin-4-yl)-4H-1'-azaspiro[oxazole-5,3'-bicyclo[2.2.2]octan]-2-amine, a potent and selective α7 nAChR partial agonist, was demonstrated to improve cognition in the mouse novel object recognition (NOR) model of episodic memory.


Assuntos
Desenho de Drogas , Octanos/síntese química , Pirimidinas/síntese química , Compostos de Espiro/síntese química , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Cognição/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Modelos Animais de Doenças , Camundongos , Estrutura Molecular , Octanos/química , Octanos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Relação Estrutura-Atividade
9.
Eur J Pharmacol ; 799: 16-25, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28132910

RESUMO

The alpha7 (α7) nicotinic acetylcholine receptor is a therapeutic target for cognitive disorders. Here we describe 3-(3,4-difluorophenyl)-N-(1-(6-(4-(pyridin-2-yl)piperazin-1-yl)pyrazin-2-yl)ethyl)propanamide (B-973), a novel piperazine-containing molecule that acts as a positive allosteric modulator of the α7 receptor. We characterize the action of B-973 on the α7 receptor using electrophysiology and radioligand binding. At 0.1mM acetylcholine, 1µM B-973 potentiated peak acetylcholine-induced currents 6-fold relative to maximal acetylcholine (3mM) and slowed channel desensitization, resulting in a 6900-fold increase in charge transfer. The EC50 of B-973 was approximately 0.3µM at acetylcholine concentrations ranging from 0.03 to 3mM. At a concentration of 1µM, B-973 shifted the acetylcholine EC50 of peak currents from 0.30mM in control to 0.007mM. B-973 slowed channel deactivation upon acetylcholine removal (τ=50s) and increased the affinity of the α7 agonist [3H]A-585539. In the absence of exogenously added acetylcholine, application of B-973 at concentrations >1µM induced large methyllycaconitine-sensitive currents, suggesting B-973 can function as an Ago-PAM at high concentrations. B-973 will be a useful probe for investigating the biological consequences of increasing α7 receptor activity through allosteric modulation.


Assuntos
Fenilpropionatos/farmacologia , Piperazinas/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Acetilcolina/farmacologia , Regulação Alostérica/efeitos dos fármacos , Relação Dose-Resposta a Droga , Descoberta de Drogas , Células HEK293 , Humanos , Cinética
10.
Bioorg Med Chem Lett ; 27(3): 578-581, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27993517

RESUMO

We describe the synthesis of quinuclidine-containing spiroguanidines and their utility as α7 neuronal nicotinic acetylcholine receptor (nAChR) partial agonists. The convergent synthetic route developed for this study allowed for rapid SAR investigation and provided access to a structurally diverse set of analogs. A potent and selective α7 nAChR partial agonist, N-(6-methyl-1,3-benzoxazol-2-yl)-3',5'-dihydro-4-azaspiro[bicyclo[2.2.2]octane-2,4'-imidazole]-2'-amine (BMS-910731, 16), was identified. This compound induced immediate early genes c-fos and Arc in a preclinical rodent model of α7 nAChR-derived cellular activation and plasticity. Importantly, the ability to incorporate selectivity for the α7 nACh receptor over the 5-HT3A receptor in this series suggested a significant difference in steric requirements between the two receptors.


Assuntos
Guanidina/farmacologia , Quinuclidinas/farmacologia , Compostos de Espiro/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Relação Dose-Resposta a Droga , Guanidina/análogos & derivados , Guanidina/química , Humanos , Estrutura Molecular , Quinuclidinas/química , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
11.
J Med Chem ; 59(24): 11171-11181, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27958732

RESUMO

The design and synthesis of a series of quinuclidine-containing spirooxazolidines ("spiroimidates") and their utility as α7 nicotinic acetylcholine receptor partial agonists are described. Selected members of the series demonstrated excellent selectivity for α7 over the highly homologous 5-HT3A receptor. Modification of the N-spiroimidate heterocycle substituent led to (1S,2R,4S)-N-isoquinolin-3-yl)-4'H-4-azaspiro[bicyclo[2.2.2]octane-2,5'oxazol]-2'-amine (BMS-902483), a potent α7 partial agonist, which improved cognition in preclinical rodent models.


Assuntos
Ciclo-Octanos/farmacologia , Desenho de Drogas , Agonistas Nicotínicos/farmacologia , Compostos de Espiro/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Animais , Ciclo-Octanos/síntese química , Ciclo-Octanos/química , Relação Dose-Resposta a Droga , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Estrutura Molecular , Agonistas Nicotínicos/síntese química , Agonistas Nicotínicos/química , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
12.
J Pharmacol Exp Ther ; 358(1): 138-50, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27189973

RESUMO

The pharmacokinetics, pharmacodynamics, safety, and tolerability of BMS-932481, a γ-secretase modulator (GSM), were tested in healthy young and elderly volunteers after single and multiple doses. BMS-932481 was orally absorbed, showed dose proportionality after a single dose administration, and had approximately 3-fold accumulation after multiple dosing. High-fat/caloric meals doubled the Cmax and area under the curve and prolonged Tmax by 1.5 hours. Consistent with the preclinical pharmacology of GSMs, BMS-932481 decreased cerebrospinal fluid (CSF) Aß39, Aß40, and Aß42 while increasing Aß37 and Aß38, thereby providing evidence of γ-secretase enzyme modulation rather than inhibition. In plasma, reductions in Aß40 and Aß42 were observed with no change in total Aß; in CSF, modest decreases in total Aß were observed at higher dose levels. Increases in liver enzymes were observed at exposures associated with greater than 70% CSF Aß42 lowering after multiple dosing. Although further development was halted due to an insufficient safety margin to test the hypothesis for efficacy of Aß lowering in Alzheimer's disease, this study demonstrates that γ-secretase modulation is achievable in healthy human volunteers and supports further efforts to discover well tolerated GSMs for testing in Alzheimer's disease and other indications.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides , Compostos de Anilina/farmacologia , Compostos de Anilina/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/farmacocinética , Adolescente , Adulto , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina/efeitos adversos , Compostos de Anilina/química , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/química , Área Sob a Curva , Cromatografia Líquida , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Limite de Detecção , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Pirimidinas/efeitos adversos , Pirimidinas/química , Adulto Jovem
13.
J Pharmacol Exp Ther ; 358(1): 125-37, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27189974

RESUMO

The amyloid-ß peptide (Aß)-in particular, the 42-amino acid form, Aß1-42-is thought to play a key role in the pathogenesis of Alzheimer's disease (AD). Thus, several therapeutic modalities aiming to inhibit Aß synthesis or increase the clearance of Aß have entered clinical trials, including γ-secretase inhibitors, anti-Aß antibodies, and amyloid-ß precursor protein cleaving enzyme inhibitors. A unique class of small molecules, γ-secretase modulators (GSMs), selectively reduce Aß1-42 production, and may also decrease Aß1-40 while simultaneously increasing one or more shorter Aß peptides, such as Aß1-38 and Aß1-37. GSMs are particularly attractive because they do not alter the total amount of Aß peptides produced by γ-secretase activity; they spare the processing of other γ-secretase substrates, such as Notch; and they do not cause accumulation of the potentially toxic processing intermediate, ß-C-terminal fragment. This report describes the translation of pharmacological activity across species for two novel GSMs, (S)-7-(4-fluorophenyl)-N2-(3-methoxy-4-(3-methyl-1H-1,2,4-triazol-1-yl)phenyl)-N4-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidine-2,4-diamine (BMS-932481) and (S,Z)-17-(4-chloro-2-fluorophenyl)-34-(3-methyl-1H-1,2,4-triazol-1-yl)-16,17-dihydro-15H-4-oxa-2,9-diaza-1(2,4)-cyclopenta[d]pyrimidina-3(1,3)-benzenacyclononaphan-6-ene (BMS-986133). These GSMs are highly potent in vitro, exhibit dose- and time-dependent activity in vivo, and have consistent levels of pharmacological effect across rats, dogs, monkeys, and human subjects. In rats, the two GSMs exhibit similar pharmacokinetics/pharmacodynamics between the brain and cerebrospinal fluid. In all species, GSM treatment decreased Aß1-42 and Aß1-40 levels while increasing Aß1-38 and Aß1-37 by a corresponding amount. Thus, the GSM mechanism and central activity translate across preclinical species and humans, thereby validating this therapeutic modality for potential utility in AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Compostos de Anilina/farmacologia , Compostos de Anilina/farmacocinética , Encéfalo/efeitos dos fármacos , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/farmacocinética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/genética , Compostos de Anilina/química , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Hidrocarbonetos Aromáticos com Pontes/química , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Macaca fascicularis , Pirimidinas/química , Ratos Sprague-Dawley , Receptores Notch/metabolismo , Especificidade da Espécie , Distribuição Tecidual
15.
Bioorg Med Chem Lett ; 25(22): 5040-7, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26497283

RESUMO

The synthesis, evaluation, and structure-activity relationships of a class of acyl guanidines which inhibit the BACE-1 enzyme are presented. The prolinyl acyl guanidine chemotype (7c), unlike compounds of the parent isothiazole chemotype (1), yielded compounds with good agreement between their enzymatic and cellular potency as well as a reduced susceptibility to P-gp efflux. Further improvements in potency and P-gp ratio were realized via a macrocyclization strategy. The in vivo profile in wild-type mice and P-gp effects for the macrocyclic analog 21c is presented.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Guanidinas/farmacologia , Compostos Macrocíclicos/farmacologia , Prolina/análogos & derivados , Prolina/farmacologia , Inibidores de Proteases/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Peptídeos beta-Amiloides/biossíntese , Animais , Células CACO-2 , Catepsina D/antagonistas & inibidores , Catepsina E/antagonistas & inibidores , Cães , Guanidinas/síntese química , Humanos , Compostos Macrocíclicos/síntese química , Células Madin Darby de Rim Canino , Masculino , Camundongos , Simulação de Acoplamento Molecular , Pepsina A/antagonistas & inibidores , Prolina/síntese química , Inibidores de Proteases/síntese química
16.
J Labelled Comp Radiopharm ; 57(10): 600-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25196195

RESUMO

Bristol-Myers Squibb and others are developing drugs that target novel mechanisms to combat Alzheimer's disease. γ-Secretase inhibitors are one class of potential therapies that have received considerable attention. (R)-2-(4-Chloro-N-(2-fluoro-4-(1,2,4-oxadiazol-3-yl)benzyl)phenylsulfonamido)-5,5,5-trifluoropentanamide (Avagacestat) is a γ-secretase-inhibiting drug that has been investigated by Bristol-Myers Squibb in preclinical and clinical studies. An important step in the development process was the synthesis of a carbon-14-labeled analog for use in a human absorption, distribution, metabolism, and excretion study and a stable isotope labeled analog for use as a standard in bioanalytical assays to accurately quantify the concentration of the drug in biological samples. Carbon-14 labeled Avagacestat was synthesized in seven steps in a 33% overall yield from carbon-14 labeled potassium cyanide. A total of 5.95 mCi was prepared with a specific activity of 0.81 µCi/mg and a radiochemical purity of 99.9%. (13) C6 -Labeled Avagacestat was synthesized in three steps in a 15% overall yield from 4-chloro[(13) C6 ]aniline. A total of 585 mg was prepared with a ultraviolet purity of 99.9%.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Oxidiazóis/síntese química , Compostos Radiofarmacêuticos/síntese química , Sulfonamidas/síntese química , Radioisótopos de Carbono/química
17.
Int J Alzheimers Dis ; 2014: 431858, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25097793

RESUMO

Alzheimer's disease is the most prevalent cause of dementia and is associated with accumulation of amyloid-ß peptide (Aß), particularly the 42-amino acid Aß1-42, in the brain. Aß1-42 levels can be decreased by γ-secretase modulators (GSM), which are small molecules that modulate γ-secretase, an enzyme essential for Aß production. BMS-869780 is a potent GSM that decreased Aß1-42 and Aß1-40 and increased Aß1-37 and Aß1-38, without inhibiting overall levels of Aß peptides or other APP processing intermediates. BMS-869780 also did not inhibit Notch processing by γ-secretase and lowered brain Aß1-42 without evidence of Notch-related side effects in rats. Human pharmacokinetic (PK) parameters were predicted through allometric scaling of PK in rat, dog, and monkey and were combined with the rat pharmacodynamic (PD) parameters to predict the relationship between BMS-869780 dose, exposure and Aß1-42 levels in human. Off-target and safety margins were then based on comparisons to the predicted exposure required for robust Aß1-42 lowering. Because of insufficient safety predictions and the relatively high predicted human daily dose of 700 mg, further evaluation of BMS-869780 as a potential clinical candidate was discontinued. Nevertheless, BMS-869780 demonstrates the potential of the GSM approach for robust lowering of brain Aß1-42 without Notch-related side effects.

18.
Psychopharmacology (Berl) ; 231(4): 673-83, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24057763

RESUMO

RATIONALE: Attentional set shifting, a measure of executive function, is impaired in schizophrenia patients. Current standard of care has little therapeutic benefit for treating cognitive dysfunction in schizophrenia; therefore, novel drugs and animal models for testing novel therapies are needed. The NMDA receptor antagonist, MK-801, produces deficits in a rat maze-based set-shifting paradigm, an effect which parallels deficits observed on tests of executive function in schizophrenia patients. Alpha7 nicotinic acetylcholine receptor (nAChR) agonists, currently under clinical development by several companies, show promise in treating cognitive symptoms in schizophrenia patients and can improve cognition in various animal models. OBJECTIVES: The objectives of the present study were to determine whether the MK-801 deficit in set shifting could be reproduced in a drug discovery setting and to determine whether cognitive improvement could be detected for the first time in this task with alpha7 nAChR agonists. RESULTS: The data presented here replicate findings that a systemic injection of the NMDA receptor antagonist MK-801 can induce a deficit in set shifting in rats. Furthermore, the deficit could be reversed by the atypical antipsychotic clozapine as well as by several alpha7 nAch receptor agonists (SSR-180711, PNU-282987, GTS-21) with varying in vitro properties. CONCLUSIONS: Results indicate that the MK-801 set-shift assay is a useful preclinical tool for measuring prefrontal cortical function in rodents and can be used to identify novel mechanisms for the potential treatment of cognitive deficits in schizophrenia.


Assuntos
Antipsicóticos/farmacologia , Atenção/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Enquadramento (Psicologia) , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Benzamidas/farmacologia , Compostos de Benzilideno/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Clozapina/farmacologia , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/etiologia , Maleato de Dizocilpina , Relação Dose-Resposta a Droga , Descoberta de Drogas/métodos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Testes Neuropsicológicos , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico
19.
Bioorg Med Chem Lett ; 23(6): 1684-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23414838

RESUMO

High throughput screening led to the identification of a novel series of quinolone α7 nicotinic acetylcholine receptor (nAChR) agonists. Optimization of an HTS hit (1) led to 4-phenyl-1-(quinuclidin-3-ylmethyl)quinolin-2(1H)-one, which was found to be potent and selective. Poor brain penetrance in this series was attributed to transporter-mediated efflux, which was in turn due to high pKa. A novel 4-fluoroquinuclidine significantly lowered the pKa of the quinuclidine moiety, reducing efflux as measured by a Caco-2 assay.


Assuntos
Agonistas Nicotínicos/química , Quinolonas/química , Receptores Nicotínicos/química , Animais , Células CACO-2 , Avaliação Pré-Clínica de Medicamentos , Humanos , Cinética , Agonistas Nicotínicos/síntese química , Agonistas Nicotínicos/metabolismo , Quinolonas/síntese química , Quinolonas/metabolismo , Ratos , Receptores Nicotínicos/metabolismo , Relação Estrutura-Atividade , Receptor Nicotínico de Acetilcolina alfa7
20.
J Pharmacol Exp Ther ; 344(3): 686-95, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23275065

RESUMO

A hallmark of Alzheimer's disease (AD) pathology is the accumulation of brain amyloid ß-peptide (Aß), generated by γ-secretase-mediated cleavage of the amyloid precursor protein (APP). Therefore, γ-secretase inhibitors (GSIs) may lower brain Aß and offer a potential new approach to treat AD. As γ-secretase also cleaves Notch proteins, GSIs can have undesirable effects due to interference with Notch signaling. Avagacestat (BMS-708163) is a GSI developed for selective inhibition of APP over Notch cleavage. Avagacestat inhibition of APP and Notch cleavage was evaluated in cell culture by measuring levels of Aß and human Notch proteins. In rats, dogs, and humans, selectivity was evaluated by measuring plasma blood concentrations in relation to effects on cerebrospinal fluid (CSF) Aß levels and Notch-related toxicities. Measurements of Notch-related toxicity included goblet cell metaplasia in the gut, marginal-zone depletion in the spleen, reductions in B cells, and changes in expression of the Notch-regulated hairy and enhancer of split homolog-1 from blood cells. In rats and dogs, acute administration of avagacestat robustly reduced CSF Aß40 and Aß42 levels similarly. Chronic administration in rats and dogs, and 28-day, single- and multiple-ascending-dose administration in healthy human subjects caused similar exposure-dependent reductions in CSF Aß40. Consistent with the 137-fold selectivity measured in cell culture, we identified doses of avagacestat that reduce CSF Aß levels without causing Notch-related toxicities. Our results demonstrate the selectivity of avagacestat for APP over Notch cleavage, supporting further evaluation of avagacestat for AD therapy.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Precursor de Proteína beta-Amiloide/antagonistas & inibidores , Oxidiazóis/farmacologia , Sulfonamidas/farmacologia , Adolescente , Adulto , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Células Cultivadas , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
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