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1.
Curr Med Res Opin ; 38(5): 777-784, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35262430

RESUMO

OBJECTIVE: Network meta-analysis was used to derive estimates of the relative efficacy of inclisiran, evolocumab, alirocumab, bempedoic acid, and ezetimibe in patients with hypercholesterolemia and/or at increased cardiovascular risk due to elevated low-density lipoprotein cholesterol taking maximum tolerated dose statins. METHODS: Clinical trials published through February 2021 comparing percent change from baseline in low-density lipoprotein cholesterol were identified via a systematic review. Bayesian network meta-analyses were performed for patients with atherosclerotic cardiovascular disease and/or high cardiovascular risk on maximally tolerated statins in the base case, which included 23 trials. RESULTS: Results from the base-case analyses demonstrated that inclisiran, evolocumab, and alirocumab provide superior efficacy over placebo, bempedoic acid, and ezetimibe in terms of reduction in low-density lipoprotein cholesterol. Inclisiran was also comparable to alirocumab (mean difference: 0.78% [95% CrI: -8.35, 9.88]) and evolocumab (8.16%, [95% CrI: -1.82, 18.49]). Findings of a scenario which also included trials conducted in patients with heterozygous familial hypercholesterolemia were consistent with the base case. There was evidence of statistical heterogeneity across the included trials, roughly equivalent to variation of 5-10% change in low-density lipoprotein cholesterol, suggesting that any differences between treatments that were greater than 5-10% are generalizable. CONCLUSIONS: This study provides insight regarding the comparative efficacy of drugs for which no head-to-head trials exist and suggests that inclisiran, alirocumab, and evolocumab are expected to provide similar clinically meaningful improvements in low-density lipoprotein cholesterol in patients with hypercholesterolemia on maximally tolerated statins who are at increased cardiovascular risk.


Assuntos
Anticolesterolemiantes , Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Hiperlipidemias , Anticolesterolemiantes/efeitos adversos , Anticolesterolemiantes/uso terapêutico , Teorema de Bayes , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Colesterol , LDL-Colesterol , Ezetimiba/uso terapêutico , Fatores de Risco de Doenças Cardíacas , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hipercolesterolemia/complicações , Hipercolesterolemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Metanálise em Rede , Fatores de Risco , Resultado do Tratamento
2.
Facial Plast Surg ; 32(2): 219-24, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27097144

RESUMO

The stigma of nasal deformity due to a congenital cleft lip-palate has an undeniable influence on the affected patient's life. It is therefore of interest to investigate if efforts to reduce esthetic and functional impairments by rhinoplasty (single or multiple) can result in an increased satisfaction with appearance and a self-perception similar to the noncleft population. Retrospective scoring before and after rhinoplasty using the validated Derriford Appearance Scale (DAS-59) and subsequent statistical evaluation and comparison to datasets available in the literature for further classification was used. Of the 61 patients who underwent at least one rhinoplasty, 26 responded to all questions. The mean age of responders was approximately 30 years of age and the male:female ratio was 1:1.2. The scale showed a significant overall improvement after surgery. The full scale and all subscale scores of the DAS-59 were significantly reduced after surgery demonstrating an improvement in the respective categories. Most importantly, if postoperative results were compared with a population concerned and unconcerned about appearance, no difference "facial self-consciousness" of appearance was apparent. Also postoperative subscores for "general self-consciousness" (GSC) and "social self-consciousness" of appearance (SSC) showed no difference from those obtained from the population concerned about appearance. The postoperative subscore for "sexual and bodily self-consciousness" of appearance (SBSC) indicated improvement beyond the level found in the concerned control population. Due to only a low improvement in the difference compared with the subscore representing a "negative self-concept," a statistically significant difference to the concerned population remained, possibly indicating that therapy beyond surgery is needed for improvement. After rhinoplasty, the investigated group of cleft lip-palate patients with nasal deformities showed an improvement in their self-conceived appearance as measured by the DAS-59. Their assessment of self-appearance was comparable to that of a group of noncleft persons with concern about their appearance. Taken together, rhinoplasties, primary and revision, add to the psychosocial well-being and an improved self-perception enhancing quality of life and enabling a more normal life. Further research is needed to clarify how the low reduction found in the "negative self-concept" may be addressed successfully.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Nariz/anormalidades , Nariz/cirurgia , Rinoplastia , Adulto , Estética , Feminino , Seguimentos , Humanos , Masculino , Autoimagem , Fatores de Tempo , Resultado do Tratamento
3.
J Med Chem ; 58(24): 9663-79, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26551034

RESUMO

The HTS-based discovery and structure-guided optimization of a novel series of GKRP-selective GK-GKRP disrupters are revealed. Diarylmethanesulfonamide hit 6 (hGK-hGKRP IC50 = 1.2 µM) was optimized to lead compound 32 (AMG-0696; hGK-hGKRP IC50 = 0.0038 µM). A stabilizing interaction between a nitrogen atom lone pair and an aromatic sulfur system (nN → σ*S-X) in 32 was exploited to conformationally constrain a biaryl linkage and allow contact with key residues in GKRP. Lead compound 32 was shown to induce GK translocation from the nucleus to the cytoplasm in rats (IHC score = 0; 10 mg/kg po, 6 h) and blood glucose reduction in mice (POC = -45%; 100 mg/kg po, 3 h). X-ray analyses of 32 and several precursors bound to GKRP were also obtained. This novel disrupter of GK-GKRP binding enables further exploration of GKRP as a potential therapeutic target for type II diabetes and highlights the value of exploiting unconventional nonbonded interactions in drug design.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glucoquinase/metabolismo , Hipoglicemiantes/química , Sulfonamidas/química , Tiofenos/química , Transporte Ativo do Núcleo Celular , Animais , Glicemia/metabolismo , Núcleo Celular/metabolismo , Cristalografia por Raios X , Citoplasma/metabolismo , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Tiofenos/farmacocinética , Tiofenos/farmacologia
4.
J Med Chem ; 58(1): 480-511, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25469863

RESUMO

The development and optimization of a series of quinolinylpurines as potent and selective PI3Kδ kinase inhibitors with excellent physicochemical properties are described. This medicinal chemistry effort led to the identification of 1 (AMG319), a compound with an IC50 of 16 nM in a human whole blood assay (HWB), excellent selectivity over a large panel of protein kinases, and a high level of in vivo efficacy as measured by two rodent disease models of inflammation.


Assuntos
Adenosina/farmacologia , Doenças Autoimunes/prevenção & controle , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Inflamação/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/farmacologia , Adenosina/química , Adenosina/metabolismo , Animais , Células Cultivadas , Classe I de Fosfatidilinositol 3-Quinases/química , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Cristalografia por Raios X , Modelos Animais de Doenças , Descoberta de Drogas , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Quinolinas/química , Quinolinas/metabolismo , Ratos Endogâmicos Lew , Células Sf9 , Relação Estrutura-Atividade
5.
Front Psychol ; 5: 1390, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25540629

RESUMO

This study explores the emergence of triadic interactions through the example of book sharing. As part of a naturalistic study, 10 infants were visited in their homes from 3-12 months. We report that (1) book sharing as a form of infant-caregiver-object interaction occurred from as early as 3 months. Using qualitative video analysis at a micro-level adapting methodologies from conversation and interaction analysis, we demonstrate that caregivers and infants practiced book sharing in a highly co-ordinated way, with caregivers carving out interaction units and shaping actions into action arcs and infants actively participating and co-ordinating their attention between mother and object from the beginning. We also (2) sketch a developmental trajectory of book sharing over the first year and show that the quality and dynamics of book sharing interactions underwent considerable change as the ecological situation was transformed in parallel with the infants' development of attention and motor skills. Social book sharing interactions reached an early peak at 6 months with the infants becoming more active in the coordination of attention between caregiver and book. From 7 to 9 months, the infants shifted their interest largely to solitary object exploration, in parallel with newly emerging postural and object manipulation skills, disrupting the social coordination and the cultural frame of book sharing. In the period from 9 to 12 months, social book interactions resurfaced, as infants began to effectively integrate manual object actions within the socially shared activity. In conclusion, to fully understand the development and qualities of triadic cultural activities such as book sharing, we need to look especially at the hitherto overlooked early period from 4 to 6 months, and investigate how shared spaces of meaning and action are structured together in and through interaction, creating the substrate for continuing cooperation and cultural learning.

6.
Bioorg Med Chem ; 22(23): 6570-6585, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25456383

RESUMO

We report the discovery of a novel series of 2-(3-alkoxy-1-azetidinyl) quinolines as potent and selective PDE10A inhibitors. Structure-activity studies improved the solubility (pH 7.4) and maintained high PDE10A activity compared to initial lead compound 3, with select compounds demonstrating good oral bioavailability. X-ray crystallographic studies revealed two distinct binding modes to the catalytic site of the PDE10A enzyme. An ex vivo receptor occupancy assay in rats demonstrated that this series of compounds covered the target within the striatum.


Assuntos
Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Quinolinas/farmacologia , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/química , Quinolinas/síntese química , Quinolinas/química , Solubilidade , Relação Estrutura-Atividade
7.
Eur J Med Chem ; 80: 364-82, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24793884
8.
Bioorg Med Chem Lett ; 23(23): 6396-400, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24120542

RESUMO

A series of aminooxadiazoles was optimized for inhibition of Cdc7. Early lead isoquinoline 1 suffered from modest cell potency (cellular IC50=0.71 µM measuring pMCM2), low selectivity against structurally related kinases, and high IV clearance in rats (CL=18 L/h/kg). Extensive optimization resulted in azaindole 26 (Cdc7 IC50=1.1 nM, pMCM2 IC50=32 nM) that demonstrated robust lowering of pMCM2 in a mouse pharmacodynamic (PD) model when dosed orally. Modifications to improve the pharmacokinetic profile of this series were guided by trapping experiments with glutathione in rat hepatocytes.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Oxidiazóis/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Nus , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Philos Trans R Soc Lond B Biol Sci ; 368(1628): 20130063, 2013 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-24018725

RESUMO

When watching an actor manipulate objects, observers, like the actor, naturally direct their gaze to each object as the hand approaches and typically maintain gaze on the object until the hand departs. Here, we probed the function of observers' eye movements, focusing on two possibilities: (i) that observers' gaze behaviour arises from processes involved in the prediction of the target object of the actor's reaching movement and (ii) that this gaze behaviour supports the evaluation of mechanical events that arise from interactions between the actor's hand and objects. Observers watched an actor reach for and lift one of two presented objects. The observers' task was either to predict the target object or judge its weight. Proactive gaze behaviour, similar to that seen in self-guided action-observation, was seen in the weight judgement task, which requires evaluating mechanical events associated with lifting, but not in the target prediction task. We submit that an important function of gaze behaviour in self-guided action observation is the evaluation of mechanical events associated with interactions between the hand and object. By comparing predicted and actual mechanical events, observers, like actors, can gain knowledge about the world, including information about objects they may subsequently act upon.


Assuntos
Antecipação Psicológica/fisiologia , Atenção/fisiologia , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Análise de Variância , Feminino , Mãos , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação
10.
Exp Brain Res ; 228(2): 221-34, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23681295

RESUMO

The ability to predict accurately the weights of objects is essential for skilled and dexterous manipulation. A potentially important source of information about object weight is through the observation of other people lifting objects. Here, we tested the hypothesis that when watching an actor lift an object, people naturally learn the object's weight and use this information to scale forces when they subsequently lift the object themselves. Participants repeatedly lifted an object in turn with an actor. Object weight unpredictably changed between 2 and 7 N every 5th to 9th of the actor's lifts, and the weight lifted by the participant always matched that previously lifted by the actor. Even though the participants were uninformed about the structure of the experiment, they appropriately adapted their lifting force in the first trial after a weight change. Thus, participants updated their internal representation about the object's weight, for use in action, when watching a single lift performed by the actor. This ability presumably involves the comparison of predicted and actual sensory information related to actor's actions, a comparison process that is also fundamental in action.


Assuntos
Adaptação Fisiológica/fisiologia , Comportamento Imitativo/fisiologia , Remoção , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Feminino , Humanos , Masculino
11.
Bioorg Med Chem Lett ; 23(7): 2056-60, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23481650

RESUMO

Cdc7 kinase is responsible for the initiation and regulation of DNA replication and has been proposed as a target for cancer therapy. We have identified a class of Cdc7 inhibitors based on a substituted indole core. Synthesis of focused indole and azaindole analogs yielded potent and selective 5-azaindole Cdc7 inhibitors with improved intrinsic metabolic stability (ie 36). In parallel, quantum mechanical conformational analysis helped to rationalize SAR observations, led to a proposal of the preferred binding conformation in the absence of co-crystallography data, and allowed the design of 7-azaindole 37 as a second lead in this series.


Assuntos
Compostos Aza/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Indóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Compostos Aza/síntese química , Compostos Aza/química , Proteínas de Ciclo Celular/metabolismo , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Relação Estrutura-Atividade
13.
Org Lett ; 12(4): 792-5, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20099864

RESUMO

An efficient and convenient method for the synthesis of [1,2,4]triazolo[4,3-a]pyridines was exemplified by the synthesis of 20 analogues bearing a variety of substituents at the 3-position. The methodology involves a palladium-catalyzed addition of hydrazides to 2-chloropyridine, which occurs chemoselectively at the terminal nitrogen atom of the hydrazide, followed by dehydration in acetic acid under microwave irradiation.


Assuntos
Técnicas de Química Combinatória , Hidrazinas/química , Paládio/química , Piridinas/química , Piridinas/síntese química , Triazóis/síntese química , Ácido Acético/química , Catálise , Ciclização , Micro-Ondas , Estrutura Molecular , Triazóis/química
14.
J Med Chem ; 52(22): 7044-53, 2009 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19856920

RESUMO

Tumor protein 53 (p53) is a critical regulator of cell cycle and apoptosis that is frequently disabled in human tumors. In many tumor types, p53 is deleted or mutated, but in others p53 is inactivated by overexpression or amplification of its negative regulator mouse double minute 2 (MDM2). A high-throughput screening effort identified 6,7-bis(4-bromophenyl)-7,12-dihydro-6H-chromeno[4,3-d][1,2,4]triazolo[1,5-a]pyrimidine as a potent inhibitor of the MDM2-p53 protein-protein interaction. This screening hit was found to be chemically unstable and difficult to handle due to poor DMSO solubility. Co-crystallization with the target protein helped to direct further optimization and provided a tractable lead series of novel MDM2-p53 inhibitors. In cellular assays, these compounds were shown to upregulate p53 protein levels and p53 signaling and to cause p53-dependent inhibition of proliferation and apoptosis.


Assuntos
Descoberta de Drogas , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirimidinas/química , Pirimidinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células HCT116 , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Conformação Molecular , Ligação Proteica/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
15.
J Am Chem Soc ; 131(11): 3840-1, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-19249829

RESUMO

A convergent synthesis of the marine natural product (+)-peloruside has been reported. This target has been assembled through the successive application of two methyl ketone boron aldol addition reactions to the latent C(7)-C(11) dialdehyde synthon. This approach afforded a 22-step synthesis of this natural product. The influence of resident stereocenters on aldol reaction diastereoselection has been examined in detail.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Lactonas/síntese química , Álcoois , Aldeídos , Animais , Produtos Biológicos/síntese química , Poríferos/química , Estereoisomerismo , Moduladores de Tubulina/síntese química
16.
J Med Chem ; 51(20): 6271-9, 2008 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-18817365

RESUMO

Investigations into the structure-activity relationships (SAR) of a series of phthalazine-based inhibitors of p38 are described. These efforts originated from quinazoline 1 and through rational design led to the development of a series of orally bioavailable, potent, and selective inhibitors. Kinase selectivity was achieved by exploiting a collection of interactions with p38alpha including close contact to Ala157, occupation of the hydrophobic gatekeeper pocket, and a residue flip with Gly110. Substitutions on the phthalazine influenced the pharmacokinetic properties, of which compound 16 displayed the most desirable profile. Oral dosing (0.03 mg/kg) of 16 in rats 1 h prior to LPS challenge gave a >50% decrease in TNFalpha production.


Assuntos
Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Ftalazinas/química , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Animais , Células Cultivadas , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Proteína Quinase 14 Ativada por Mitógeno/química , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Modelos Moleculares , Estrutura Molecular , Ftalazinas/síntese química , Inibidores de Proteínas Quinases/síntese química , Quinolinas/síntese química , Quinolinas/química , Quinolinas/farmacologia , Ratos , Sensibilidade e Especificidade , Relação Estrutura-Atividade
17.
Perception ; 36(7): 1066-83, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17844972

RESUMO

In a series of exploratory experiments we investigated interrelations between structure and shape of architectural indoor spaces on the one hand, and affective experience and navigation behaviour on the other hand. For this, isovist-based descriptions of 16 virtual indoor scenes were correlated with behavioural data from the experimental tasks. For all tasks-two active navigation tasks and an introspective appraisal of experiential qualities--strong correlations between subjects' behaviour and a small set of quantitative measurands derived from the isovists were found. The outcomes suggest that isovist analysis captures behaviourally relevant properties of space and is therefore a promising general means for predicting central experiential qualities of architecture and navigation behaviour.


Assuntos
Locomoção , Percepção Espacial , Adulto , Emoções , Planejamento Ambiental , Feminino , Humanos , Masculino , Orientação , Desempenho Psicomotor , Tempo de Reação , Sensação , Fatores Sexuais , Comportamento Espacial , Interface Usuário-Computador
18.
Acc Chem Res ; 39(7): 433-42, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16846207

RESUMO

Small peptides exhibit a wide range of biological activities, but although there are some notable exceptions, they are not generally useful as drugs. This has spurred widespread interest in designing peptidomimetics and introducing them as replacements of portions of native peptides to enhance their biological properties. Special attention has been focused upon rigid replacements because of their potential to preorganize the resulting pseudopeptide in a conformation corresponding to its bound structure. Toward this goal, we invented trisubstituted cyclopropanes as novel peptidomimetics, anticipating that the cyclopropane ring would locally orient the backbone and the corresponding amino acid side chain in the biologically active conformation. Selected aspects of the syntheses and applications of these cyclopropane-derived peptidomimetics are presented in this Account.


Assuntos
Ciclopropanos/química , Mimetismo Molecular , Peptídeos/síntese química , Inibidores de Metaloproteinases de Matriz , Modelos Moleculares , Peptídeos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/química
19.
J Org Chem ; 67(12): 4062-75, 2002 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-12054939

RESUMO

We have previously used trisubstituted cyclopropanes as peptide replacements to induce conformational constraints in known pseudopeptide inhibitors of a number of important enzymes. Cyclopropane-derived peptide mimics are novel in that they are among the few replacements that locally orient the peptide backbone and the amino acid side chain in a predefined manner. Although these dipeptide isosteres have been employed to orient amino acid side chains mimicking the gauche(-) conformation of chi(1)-space, their ability to project the side chains into an anti orientation has not been evaluated. As a first step toward this goal, the conformationally constrained pseudopeptides 8 and 10 and their corresponding flexible analogues 9 and 11 were prepared and tested as inhibitors of matrix metalloproteinases (MMPs). These compounds are analogues of 4 and 5, which were known to be potent MMP inhibitors. The anti orientations of the isopropyl side chain in 8 and the aromatic ring in 10 relative to the peptide backbone substituents on the cyclopropane were predicted to correspond to the known orientations of the P1' and P2' side chains of 5 when bound to MMPs. Hence, 8 and 10 were designed explicitly to probe topological features of the S1' or the S2' binding pockets of the MMPs. They were also designed to explore the importance of the P1'-P2' amide group, which is known to form highly conserved hydrogen bonds in several MMP-inhibitor complexes, and the viability of introducing a retro amide linkage between P2' and P3'. Pseudopeptides 8 and 9 were found to be weak competitive inhibitors of a series of MMPs. Any entropically favorable conformational constraints that were induced by the cyclopropane in 8 were thus overwhelmed by the loss of the hydrogen bonding capability associated with the P1'-P2' amide group. On the other hand, compounds 10 and 11, which contain a P2'-P3' retro amide group, were modest competitive inhibitors of a series of MMPs. The results obtained for 10 and 11 suggest that there may be a loss of hydrogen bonding capability associated with introducing the P2'-P3' retro amide group. However, because the conformationally constrained pseudopeptide 10 was significantly more potent than its flexible analogue 11, trisubstituted cyclopropanes related to 3 may serve as useful rigid dipeptide replacements in some biologically active pseudopeptides.


Assuntos
Ciclopropanos/química , Desenho de Fármacos , Inibidores de Metaloproteinases de Matriz , Mimetismo Molecular , Peptídeos , Inibidores de Proteases/síntese química , Sequência de Aminoácidos , Sítios de Ligação , Técnicas de Química Combinatória , Avaliação Pré-Clínica de Medicamentos , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Oxirredução , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Análise Espectral , Relação Estrutura-Atividade , Especificidade por Substrato
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