RESUMO
The difluoromethyl-allo-threonyl hydroxamate-based compound LPC-058 is a potent inhibitor of UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine deacetylase (LpxC) in Gram-negative bacteria. A scalable synthesis of this compound is described. The key step in the synthetic sequence is a transition metal/base-catalyzed aldol reaction of methyl isocyanoacetate and difluoroacetone, giving rise to 4-(methoxycarbonyl)-5,5-disubstituted 2-oxazoline. A simple NMR-based determination of enantiomeric purity is also described.
Assuntos
Amidoidrolases/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/farmacologia , Benzamidas/síntese química , Benzamidas/farmacologia , Catálise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/enzimologia , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação MolecularRESUMO
The cannabinoid 1 (CB1) allosteric modulator, 5-chloro-3-ethyl-1H-indole-2-carboxylic acid [2-(4-piperidin-1-yl-phenyl)-ethyl]-amide) (ORG27569), has the paradoxical effect of increasing the equilibrium binding of [(3)H](-)-3-[2-hydroxyl-4-(1,1-dimethylheptyl)phenyl]-4-[3-hydroxylpropyl]cyclohexan-1-ol (CP55,940, an orthosteric agonist) while at the same time decreasing its efficacy (in G protein-mediated signaling). ORG27569 also decreases basal signaling, acting as an inverse agonist for the G protein-mediated signaling pathway. In ligand displacement assays, ORG27569 can displace the CB1 antagonist/inverse agonist, N-(piperidiny-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide(SR141716A). The goal of this work was to identify the binding site of ORG27569 at CB1. To this end, we used computation, synthesis, mutation, and functional studies to identify the ORG27569-binding site in the CB1 TMH3-6-7 region. This site is consistent with the results of K3.28(192)A, F3.36(200)A, W5.43(279)A, W6.48(356)A, and F3.25(189)A mutation studies, which revealed the ORG27569-binding site overlaps with our previously determined binding site of SR141716A but extends extracellularly. Additionally, we identified a key electrostatic interaction between the ORG27569 piperidine ring nitrogen and K3.28(192) that is important for ORG27569 to act as an inverse agonist. At this allosteric site, ORG27569 promotes an intermediate conformation of the CB1 receptor, explaining ORG27569's ability to increase equilibrium binding of CP55,940. This site also explains ORG27569's ability to antagonize the efficacy of CP55,940 in three complementary ways. 1) ORG27569 sterically blocks movements of the second extracellular loop that have been linked to receptor activation. 2) ORG27569 sterically blocks a key electrostatic interaction between the third extracellular loop residue Lys-373 and D2.63(176). 3) ORG27569 packs against TMH6, sterically hindering movements of this helix that have been shown to be important for receptor activation.
Assuntos
Antagonistas de Receptores de Canabinoides/farmacologia , Indóis/farmacologia , Simulação de Dinâmica Molecular , Piperidinas/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Regulação Alostérica/efeitos dos fármacos , Regulação Alostérica/genética , Sítios de Ligação , Antagonistas de Receptores de Canabinoides/química , Células HEK293 , Humanos , Indóis/química , Piperidinas/química , Ligação Proteica , Pirazóis , Receptor CB1 de Canabinoide/metabolismo , Rimonabanto , Transdução de Sinais/genéticaRESUMO
Despite the therapeutic promise of the subnanomolar affinity cannabinoid CB2 antagonist, 5-(4-chloro-3-methylphenyl)-1-[(4-methylphenyl)methyl]-N-[(1S,2S,4R)-1,3,3-trimethylbicyclo[2.2.1]hept-2-yl]-1H-pyrazole-3-carboxamide (SR144528, 1), little is known about its binding site interactions and no primary interaction site for 1 at CB2 has been identified. We report here the results of Glide docking studies in our cannabinoid CB2 inactive state model that were then tested via compound synthesis, binding, and functional assays. Our results show that the amide functional group of 1 is critical to its CB2 affinity and efficacy and that aromatic stacking interactions in the TMH5/6 aromatic cluster of CB2 are also important. Molecular modifications that increased the positive electrostatic potential in the region between the fenchyl and aromatic rings led to more efficacious compounds. This result is consistent with the EC-3 loop negatively charged amino acid, D275 (identified via Glide docking studies) acting as the primary interaction site for 1 and its analogues.
Assuntos
Canfanos/farmacologia , Pirazóis/farmacologia , Receptor CB2 de Canabinoide/antagonistas & inibidores , Canfanos/química , Ligação de Hidrogênio , Modelos Moleculares , Pirazóis/química , Ensaio Radioligante , Receptor CB2 de Canabinoide/químicaRESUMO
To further explore the optimum placement of the acid moiety in conformationally constrained analogs of GW 4064 1a, a series of stilbene replacements were prepared. The benzothiophene 1f and the indole 1g display the optimal orientation of the carboxylate for enhanced FXR agonist potency.
Assuntos
Isoxazóis/química , Isoxazóis/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Estilbenos/química , Estilbenos/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Humanos , Conformação Molecular , Dados de Sequência Molecular , Receptores Citoplasmáticos e Nucleares/metabolismoRESUMO
To improve on the drug properties of GSK8062 1b, a series of heteroaryl bicyclic naphthalene replacements were prepared. The quinoline 1c was an equipotent FXR agonist with improved drug developability parameters relative to 1b. In addition, analog 1c lowered body weight gain and serum glucose in a DIO mouse model of diabetes.
Assuntos
Isoxazóis/química , Naftalenos/química , Quinolinas/química , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Sítios de Ligação , Glicemia/metabolismo , Cristalografia por Raios X , Diabetes Mellitus Experimental/metabolismo , Cães , Transferência Ressonante de Energia de Fluorescência , Humanos , Isoxazóis/síntese química , Isoxazóis/farmacocinética , Ligantes , Camundongos , Conformação Molecular , Estrutura Terciária de Proteína , Quinolinas/síntese química , Quinolinas/farmacocinética , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Aumento de Peso/efeitos dos fármacosRESUMO
Two series of conformationally constrained analogs of the FXR agonist GW 4064 1 were prepared. Replacement of the metabolically labile stilbene with either benzothiophene or naphthalene rings led to the identification of potent full agonists 2a and 2g.
Assuntos
Isoxazóis/química , Naftalenos/química , Receptores Citoplasmáticos e Nucleares/agonistas , Tiofenos/química , Animais , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Humanos , Isoxazóis/farmacologia , Naftalenos/farmacocinética , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Relação Estrutura-Atividade , Tiofenos/farmacocinéticaRESUMO
A series of estrogen receptor ligands based on a 3-alkyl naphthalene scaffold was synthesized using an intramolecular enolate-alkyne cycloaromatization as the key step. Several of these compounds bearing a C6-OH group were shown to be high affinity ligands. All compounds had similar ERalpha and ERbeta binding affinity ranging from micromolar to low nanomolar.
Assuntos
Naftalenos/síntese química , Naftalenos/farmacologia , Receptores de Estrogênio/agonistas , Técnicas de Química Combinatória , Moduladores de Receptor Estrogênico/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Ligantes , Estrutura Molecular , Naftalenos/química , Moduladores Seletivos de Receptor Estrogênico/metabolismo , Relação Estrutura-AtividadeRESUMO
Starting from the known FXR agonist GW 4064 1a, a series of stilbene replacements were prepared. The 6-substituted 1-naphthoic acid 1b was an equipotent FXR agonist with improved developability parameters relative to 1a. Analog 1b also reduced the severity of cholestasis in the ANIT acute cholestatic rat model.
Assuntos
Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/farmacologia , Colestase/tratamento farmacológico , Proteínas de Ligação a DNA/agonistas , Isoxazóis/síntese química , Isoxazóis/farmacologia , Naftalenos/síntese química , Naftalenos/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Fatores de Transcrição/agonistas , Administração Oral , Animais , Ácidos Carboxílicos/química , Colestase/metabolismo , Colestase/patologia , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Modelos Animais de Doenças , Cães , Mucosa Gástrica/metabolismo , Haplorrinos , Isoxazóis/química , Camundongos , Conformação Molecular , Estrutura Molecular , Naftalenos/química , Ratos , Receptores Citoplasmáticos e Nucleares/química , Estômago/efeitos dos fármacos , Relação Estrutura-Atividade , Fatores de Transcrição/químicaRESUMO
The structure-activity relationship of 2'-pyrrole, pyrazole and triazole substituted 2-(anilinomethyl)imidazolines as alpha(1) adrenergic agonists was investigated. The size and orientation of substituents, as well as the position of the heteroatoms, were found to have a profound effect on the potency and selectivity of the molecules. Potent alpha(1A) subtype selective agonists have been identified.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 1 , Agonistas alfa-Adrenérgicos/síntese química , Agonistas alfa-Adrenérgicos/farmacologia , Pirazóis/síntese química , Pirazóis/farmacologia , Pirróis/síntese química , Pirróis/farmacologia , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/farmacologiaRESUMO
The high-throughput manual solid-phase parallel synthesis of libraries comprising thousands of discrete samples using pellicular supports (i.e. SynPhase crowns and lanterns) and a suite of novel tools and techniques is described. Key aspects of this approach include the combination of a split-split-split synthesis strategy with spatial encoding to differentiate thousands of crowns, the rapid washing and filtration of up to 48 reaction vessels in parallel, the application of an inexpensive and environmentally friendly technique to remove trifluoroacetic acid from sixteen 96-well plates in parallel, and a high-throughput method for removing cleaved crowns from reusable pin racks. Tens of thousands of discrete samples have been produced in-house using this conceptually and operationally straightforward strategy.
RESUMO
Literature reports suggest that disruption of an interhelical salt bridge is critical for alpha(1)-adrenoceptor activation, and the basic amine found in adrenergic receptor ligands is responsible for the disruption. Novel 4-(anilinomethyl)imidazoles and 4-(phenoxymethyl)imidazoles are agonists of the cloned human alpha(1)-adrenoceptors in vitro, and potent, selective alpha(1A)-adrenoceptor agonists have been identified in this series. These imidazoles demonstrate similar potencies and alpha(1)-subtype selectivities as the corresponding 2-substituted imidazolines. The extremely close SAR suggests that, in spite of the large difference in basicity, these imidazoles and imidazolines may establish the same interactions to activate alpha(1)-adrenoceptors.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 1 , Agonistas alfa-Adrenérgicos/química , Agonistas alfa-Adrenérgicos/farmacologia , Compostos de Anilina/química , Imidazóis/química , Imidazóis/farmacologia , Éteres Fenílicos/química , Humanos , Proteínas Recombinantes/agonistas , Relação Estrutura-AtividadeRESUMO
A series of 2'-alkylthio-2-(anilinomethyl)imidazolines were prepared to examine the effect of the alkyl group size, sulfur oxidation state, and phenyl ring substitution on ligand binding and agonism of alpha-adrenergic receptor subtypes alpha1a, alpha1b, alpha1d, alpha2a, and alpha2c. Binding at all receptor subtypes decreased for compounds in the sulfone oxidation state as compared to their sulfide analogues. While sulfides were generally potent, nonselective agonists, sulfones exhibited alpha1a subtype selectivity in a cell-based functional assay. Sulfone (32) was 250-7000-fold selective for alpha1a vs all other subtypes.
Assuntos
Agonistas alfa-Adrenérgicos/síntese química , Imidazóis/síntese química , Receptores Adrenérgicos alfa 1/efeitos dos fármacos , Sulfonas/síntese química , Agonistas alfa-Adrenérgicos/química , Agonistas alfa-Adrenérgicos/farmacologia , Cálcio/metabolismo , Linhagem Celular , AMP Cíclico/biossíntese , Fibroblastos/metabolismo , Humanos , Imidazóis/química , Imidazóis/farmacologia , Sulfonas/química , Sulfonas/farmacologiaRESUMO
A series of 2'-heteroaryl and 2'-oxime anilinomethylimidazolines was prepared and evaluated in in vitro functional assays for cloned human alpha1A, alpha1B, and alpha1D receptor subtypes. Potent and selective alpha1A agonists have been identified in these series.
Assuntos
Agonistas alfa-Adrenérgicos/síntese química , Imidazóis/farmacologia , Agonistas de Receptores Adrenérgicos alfa 1 , Agonistas alfa-Adrenérgicos/química , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Clonagem Molecular , Compostos Heterocíclicos , Humanos , Imidazóis/síntese química , Imidazóis/química , Oximas , Fenilefrina/metabolismo , Ligação Proteica , Ratos , Receptores Adrenérgicos alfa 1/metabolismoRESUMO
Novel 2'-heteroaryl-2-(phenoxymethyl)imidazolines have been identified as potent agonists of the cloned human alpha(1)-adrenoceptors in vitro. The nature of the 2'-heteroaryl group can have significant effects on the potency, efficacy, and subtype selectivity in this series. alpha(1A) Subtype selective agonists have been identified.