RESUMO
We encountered a dilemma in the course of studying a series of antagonists of the G-protein coupled receptor CC chemokine receptor-2 (CCR2): compounds with polar C3 side chains exhibited good ion channel selectivity but poor oral bioavailability, whereas compounds with lipophilic C3 side chains exhibited good oral bioavailability in preclinical species but poor ion channel selectivity. Attempts to solve this through the direct modulation of physicochemical properties failed. However, the installation of a protonation-dependent conformational switching mechanism resolved the problem because it enabled a highly selective and relatively polar molecule to access a small population of a conformer with lower polar surface area and higher membrane permeability. Optimization of the overall properties in this series yielded the CCR2 antagonist BMS-741672 (7), which embodied properties suitable for study in human clinical trials.
RESUMO
Fingolimod (1) is the first approved oral therapy for the treatment of relapsing remitting multiple sclerosis. While the phosphorylated metabolite of fingolimod was found to be a nonselective S1P receptor agonist, agonism specifically of S1P1 is responsible for the peripheral blood lymphopenia believed to be key to its efficacy. Identification of modulators that maintain activity on S1P1 while sparing activity on other S1P receptors could offer equivalent efficacy with reduced liabilities. We disclose in this paper a ligand-based drug design approach that led to the discovery of a series of potent tricyclic agonists of S1P1 with selectivity over S1P3 and were efficacious in a pharmacodynamic model of suppression of circulating lymphocytes. Compound 10 had the desired pharmacokinetic (PK) and pharmacodynamic (PD) profile and demonstrated maximal efficacy when administered orally in a rat adjuvant arthritis model.
Assuntos
Desenho de Fármacos , Cloridrato de Fingolimode/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Receptores de Lisoesfingolipídeo/agonistas , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Cães , Relação Dose-Resposta a Droga , Cloridrato de Fingolimode/administração & dosagem , Cloridrato de Fingolimode/química , Adjuvante de Freund/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/química , Ligantes , Linfócitos/efeitos dos fármacos , Macaca fascicularis , Masculino , Camundongos , Estrutura Molecular , Mycobacterium/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Relação Estrutura-Atividade , Distribuição TecidualRESUMO
We describe the hybridization of our previously reported acyclic and cyclic CC chemokine receptor 2 (CCR2) antagonists to lead to a new series of dual antagonists of CCR2 and CCR5. Installation of a γ-lactam as the spacer group and a quinazoline as a benzamide mimetic improved oral bioavailability markedly. These efforts led to the identification of 13d, a potent and orally bioavailable dual antagonist suitable for use in both murine and monkey models of inflammation.
RESUMO
An efficient enantioselective synthesis of benzyl (1S,2R,4R)-4-(tert-butoxycarbonylamino)-2-(hydroxymethyl)cyclohexylcarbamate 2, an essential intermediate for a series of potent CCR2 antagonists, is described. The key step in the sequence is an iodolactamization to yield the highly functionalized (1R,2S,4S,5S)-tert-butyl 2-(benzyloxycarbonylamino)-4-iodo-7-oxo-6-azabicyclo[3.2.1]octane-6-carboxylate 11. An examination of the reaction mechanism within the 2-step iodolactamization sequence led to the discovery of a single-pot transformation of increased efficiency.
Assuntos
Carbamatos/química , Carbamatos/síntese química , Cicloexanos/química , Cicloexanos/síntese química , Lactamas/química , Anidridos Ftálicos/química , Estereoisomerismo , Especificidade por SubstratoRESUMO
Conformational analysis of trans-1,2-disubstituted cyclohexane CCR3 antagonist 2 revealed that the cyclohexane linker could be replaced by an acyclic syn-alpha-methyl-beta-hydroxypropyl linker. Synthesis and biological evaluation of mono- and disubstituted propyl linkers support this conformational correlation. It was also found that the alpha-methyl group to the urea lowered protein binding and that the beta-hydroxyl group lowered affinity for CYP2D6. Ab initio calculations show that the alpha-methyl group governs the spatial orientation of three key functionalities within the molecule. alpha-Methyl-beta-hydroxypropyl urea 31 with a chemotaxis IC(50)=38 pM for eosinophils was chosen to enter clinical development for the treatment of asthma.
Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Eosinófilos/efeitos dos fármacos , Piperidinas/farmacologia , Receptores CCR3/antagonistas & inibidores , Ureia/análogos & derivados , Administração Oral , Animais , Inibidores das Enzimas do Citocromo P-450 , Cães , Eosinófilos/citologia , Ligação de Hidrogênio , Camundongos , Conformação Molecular , Piperidinas/química , Piperidinas/farmacocinética , Ratos , Relação Estrutura-Atividade , Ureia/química , Ureia/farmacocinética , Ureia/farmacologiaRESUMO
Conformational analysis of the 3-benzylpiperidine in CCR3 antagonist clinical candidate 1 (BMS-639623) predicts that the benzylpiperidine may be replaced by acyclic, conformationally stabilized, anti-1,2-disubstituted phenethyl- and phenpropylamines. Ab initio calculations, enantioselective syntheses, and evaluation in CCR3 binding and chemotaxis assays of anti-1-methyl-2-hydroxyphenethyl- and phenpropylamine-containing CCR3 antagonists support this conformational correlation.
Assuntos
Piperidinas/química , Piperidinas/farmacologia , Receptores CCR3/antagonistas & inibidores , Ureia/análogos & derivados , Ciclização , Ligação de Hidrogênio , Conformação Molecular , Ureia/química , Ureia/farmacologiaRESUMO
DPC168, a benzylpiperidine-substituted aryl urea CCR3 antagonist evaluated in clinical trials, was a relatively potent inhibitor of the 2D6 isoform of cytochrome P-450 (CYP2D6). Replacement of the cyclohexyl central ring with saturated heterocycles provided potent CCR3 antagonists with improved selectivity against CYP2D6. The favorable preclinical profile of DPC168 was maintained in an acetylpiperidine derivative, BMS-570520.
Assuntos
Compostos de Benzil/química , Compostos de Benzil/farmacologia , Inibidores do Citocromo P-450 CYP2D6 , Compostos de Fenilureia/química , Piperidinas/química , Piperidinas/farmacologia , Receptores de Quimiocinas/antagonistas & inibidores , Animais , Compostos de Benzil/síntese química , Bioensaio , Células Cultivadas , Humanos , Camundongos , Pan troglodytes , Compostos de Fenilureia/farmacologia , Piperidinas/síntese química , Receptores CCR3 , Relação Estrutura-AtividadeRESUMO
Linear unselective CCR3 antagonist leads with IC(50) values in the 200 nM range were converted into low nM binding compounds selective at CCR3 by moving the piperidine nitrogen substituent to the carbon at the 2-position of the ring. Substitution of the piperidine nitrogen with simple alkyl and acyl groups was found to improve the selectivity of this new compound class. In particular, N-{3-[(2S, 4R)-1-(propyl)-4-(4-fluorobenzyl)piperidinyl]propyl}-N'-(3-acetylphenyl)urea exhibited single digit nanomolar IC(50) values for CCR3 with >100-fold selectivity against an extensive counter screen panel.
Assuntos
Piperidinas/síntese química , Piperidinas/farmacologia , Receptores de Quimiocinas/antagonistas & inibidores , Piperidinas/química , Receptores CCR3 , Relação Estrutura-AtividadeRESUMO
CC chemokine receptor (CCR) 3 is a chemokine receptor implicated in recruiting cells, particularly eosinophils (EPhi), to the lung in episodes of allergic asthma. To investigate the efficacy of selective, small molecule antagonists of CCR3, we developed a murine model of EPhi recruitment to the lung. Murine eotaxin was delivered intranasally to mice that had previously received i.p. injections of ovalbumin (OVA), and the effects were monitored by bronchoalveolar lavage. A selective eosinophilic influx was produced in animals receiving eotaxin but not saline. Furthermore, the number of EPhi was concentration- and time-dependent. Although anti-CCR3 antibody reduced the number of EPhi, the effect of eotaxin in OVA-sensitized mice was not a direct chemotactic stimulus because mast cell deficiency (in WBB6F1-Kitw/Kitw-v mice) significantly reduced the response. Two representative small molecule CCR3 antagonists from our program were characterized as being active at mouse CCR3. They were administered p.o. to wild-type mice and found to reduce eotaxin-elicited EPhi selectively in a dose-dependent manner. Pump infusion of one of the inhibitors to achieve steady-state levels showed that efficacy was not achieved at plasma concentrations equivalent to the in vitro chemotaxis IC90 but only at much higher concentrations. To extend the results from our recruitment model, we tested one of the inhibitors in an allergenic model of airway inflammation, generated by adoptive transfer of OVA-sensitive murine T helper 2 cells and aerosolized OVA challenge of recipient mice, and found that it inhibited EPhi recruitment. We conclude that small molecule CCR3 antagonists reduce pulmonary eosinophilic inflammation elicited by chemokine or allergenic challenge.
Assuntos
Inibição de Migração Celular , Modelos Animais de Doenças , Eosinófilos/metabolismo , Pulmão/metabolismo , Receptores de Quimiocinas/antagonistas & inibidores , Hipersensibilidade Respiratória/metabolismo , Animais , Células CHO , Cricetinae , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores CCR3 , Receptores de Quimiocinas/imunologia , Receptores de Quimiocinas/metabolismo , Hipersensibilidade Respiratória/imunologiaRESUMO
Starting with our previously described(20) class of CC chemokine receptor-3 (CCR3) antagonist, we improved the potency by replacing the phenyl linker of 1 with a cyclohexyl linker and by replacing the 4-benzylpiperidine with a 3-benzylpiperidine. The resulting compound, 32, is a potent and selective antagonist of CCR3. SAR studies showed that the 3-acetylphenyl urea of 32 could be replaced with heterocyclic ureas or heterocyclic-substituted phenyl ureas and still maintain the potency (inhibition of eotaxin-induced chemotaxis) of this class of compounds in the low-picomolar range (IC(50) = 10-60 pM), representing some of the most potent CCR3 antagonists reported to date. The potency of 32 for mouse CCR3 (chemotaxis IC(50) = 41 nM) and its oral bioavailability in mice (20% F ) were adequate to assess the efficacy in animal models of allergic airway inflammation. Oral administration of 32 reduced eosinophil recruitment into the lungs in a dose-dependent manner in these animal models. On the basis of its overall potency, selectivity, efficacy, and safety profile, the benzenesulfonate salt of 32, designated DPC168, entered phase I clinical trials.
Assuntos
Cicloexanos/síntese química , Compostos de Fenilureia/síntese química , Piperidinas/síntese química , Receptores de Quimiocinas/antagonistas & inibidores , Animais , Disponibilidade Biológica , Células CHO , Células CACO-2 , Cálcio/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Cricetinae , Cicloexanos/química , Cicloexanos/farmacologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/fisiologia , Feminino , Humanos , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/imunologia , Técnicas In Vitro , Inflamação/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Permeabilidade , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Receptores CCR3 , Estereoisomerismo , Relação Estrutura-Atividade , Ureia/análogos & derivados , Ureia/síntese química , Ureia/química , Ureia/farmacologiaRESUMO
The discovery of novel and selective small molecule antagonists of the CC Chemokine Receptor-3 (CCR3) is presented. Simple conversion from a 4- to 3-benzylpiperidine gave improved selectivity for CCR3 over the serotonin 5HT(2A) receptor. Chiral resolution and exploration of mono- and disubstitution of the N-propylurea resulted in several 3-benzylpiperidine N-propylureas with CCR3 binding IC(50)s under 5 nM. Data from in vitro calcium mobilization and chemotaxis assays for these compounds ranged from high picomolar to low nanomolar EC(50)s and correlated well with antagonist binding IC(50)s.
Assuntos
Piperidinas/metabolismo , Receptores de Quimiocinas/antagonistas & inibidores , Receptores de Quimiocinas/metabolismo , Ureia/análogos & derivados , Ureia/metabolismo , Animais , Células CHO , Bovinos , Cricetinae , Piperidinas/química , Ligação Proteica/fisiologia , Receptores CCR3 , Ureia/químicaRESUMO
Structure-activity relationship (SAR) studies of initial screening hits from our corporate library of compounds and a structurally related series of CCR1 receptor antagonists were used to determine that an N-(alkyl)benzylpiperidine is an essential pharmacophore for selective CCR3 antagonists. Further SAR studies that introduced N-(ureidoalkyl) substituents improved the binding potency of these compounds from the micromolar to the low nanomolar range. This new series of compounds also displays highly potent, in vitro functional CCR3-mediated antagonism of eotaxin-induced Ca(2+) mobilization and chemotaxis of human eosinophils.
Assuntos
Antialérgicos/síntese química , Piperidinas/síntese química , Receptores de Quimiocinas/antagonistas & inibidores , Ureia/análogos & derivados , Ureia/síntese química , Animais , Antialérgicos/química , Antialérgicos/farmacologia , Células CHO , Cálcio/metabolismo , Quimiocina CCL11 , Quimiocinas CC/farmacologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Cricetinae , Eosinófilos/citologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/metabolismo , Humanos , Técnicas In Vitro , Piperidinas/química , Piperidinas/farmacologia , Receptores CCR3 , Receptores de Quimiocinas/metabolismo , Relação Estrutura-Atividade , Ureia/química , Ureia/farmacologiaRESUMO
CCR3 antagonist leads with IC(50) values in the microM range were converted into low nM binding compounds that displayed in vitro inhibition of human eosinophil chemotaxis induced by human eotaxin. In particular, 4-benzylpiperidin-1-yl-n-propylureas and erythro-3-(4-benzyl-2-(alpha-hydroxyalkyl)piperidin-1-yl)-n-propylureas (obtained via Beak reaction of N-BOC-4-benzylpiperidine) exhibited single digit nanomolar IC(50) values for CCR3.