RESUMO
Bradykinin, desArg9BK, some agonist analogues and several antagonists have been tested in isolated organs in order to identify bradykinin B2 receptor subtypes. The initial pharmacological characterization was made in the rabbit jugular vein and the guinea pig ileum, two widely used B2 preparations which have shown marked differences in their sensitivities to both agonists and antagonists. The study has then been extended to peripheral tissues (stomach, colon, urinary bladder) of four species (the rat, guinea pig, rabbit and man) and to isolated vessels (rabbit jugular vein, rabbit vena cava, guinea pig pulmonary artery, rat portal vein) in order to determine if pharmacologic receptor subtypes may be related to species. It has been shown that B2 receptors in rat and guinea pig tissues belong to a similar pharmacological entity, a receptor which is different from that mediating the responses of rabbit and human tissues. Agonists order of potency ([Hyp3]BK > BK > [Aib7]BK) obtained in the rabbit jugular vein is different from that found in the guinea pig ileum (BK < or = [Aib7]BK > [Hyp3]BK). Affinities of competitive antagonists (for instance DArg[Hyp3,DPhe7,Leu8]BK) in rabbit tissues are higher than in guinea pig and rat tissues by at least 2 log units, while the non peptidic compound WIN 64338 is more active (also by two log units) in guinea pig than in human and rabbit tissues. The non competitive long-acting antagonist HOE 140 is very potent and equally active in the four species. Some antagonists (peptides without unnatural residues, peptides with unnatural residues, non peptides) have been shown to be specific for kinin receptors and selective for the B2. Altogether, the present results a) confirm the existence of two B2 receptor subtypes, b) suggest that receptor subtypes may be species dependent and c) indicate that the B2 receptor subtype found in the rabbit is similar to that found in man.
Assuntos
Bradicinina/análogos & derivados , Bradicinina/farmacologia , Músculo Liso Vascular/fisiologia , Receptores da Bradicinina/fisiologia , Animais , Antagonistas dos Receptores da Bradicinina , Cobaias , Humanos , Íleo/efeitos dos fármacos , Íleo/fisiologia , Técnicas In Vitro , Veias Jugulares/efeitos dos fármacos , Veias Jugulares/fisiologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Especificidade de Órgãos , Coelhos , Ratos , Receptores da Bradicinina/classificação , Estômago/efeitos dos fármacos , Estômago/fisiologia , Relação Estrutura-AtividadeAssuntos
Compostos Organofosforados/síntese química , Receptores de Neurotransmissores/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Ligação Competitiva , Cobaias , Humanos , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Naftalenos/síntese química , Naftalenos/farmacologia , Compostos Organofosforados/farmacologia , Ratos , Receptores da Bradicinina , Receptores de Neurotransmissores/metabolismo , Relação Estrutura-AtividadeAssuntos
Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/síntese química , Oligopeptídeos/síntese química , Sequência de Aminoácidos , Caspase 1 , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/farmacologia , Desenho de Fármacos , Ligação de Hidrogênio , Interleucina-1/metabolismo , Cinética , Dados de Sequência Molecular , Estrutura Molecular , Oligopeptídeos/farmacologia , Pirimidinas/síntese química , Pirimidinas/farmacologiaAssuntos
Amidas/química , Cisteína Endopeptidases/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Cetonas/farmacologia , Nitrogênio/química , Sequência de Aminoácidos , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Ácido Aspártico/farmacologia , Caspase 1 , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Cetonas/metabolismo , Dados de Sequência Molecular , Relação Estrutura-AtividadeAssuntos
Azepinas/química , Inibidores Enzimáticos/síntese química , Piridazinas/química , Serpinas/síntese química , Proteínas Virais , Animais , Azepinas/farmacocinética , Cães , Desenho de Fármacos , Inibidores Enzimáticos/farmacocinética , Taxa de Depuração Metabólica , Piridazinas/farmacocinética , Serpinas/farmacocinéticaRESUMO
The solid-phase synthesis of a 10,000 member combinatorial library of 1,5-benzodiazepine-2-one derivatives is reported. The 3-amino-1,5-benzodiazepine-2-one scaffold was prepared in solution, and the benzamide nitrogen was used as a point of attachment to the resin. The 5-aniline and 3-amine were then used as points of diversity. A 10,000 member library was synthesized using the Irori directed sorting system, and after analysis of a representative sample from the library, the Irori system was used to remove the compounds of lower purity.
Assuntos
Ansiolíticos/química , Benzodiazepinonas/química , Benzodiazepinonas/síntese química , Aminas/síntese química , Aminas/química , Sequência de Aminoácidos , Técnicas de Química Combinatória/métodos , Desenho de Fármacos , Dinorfinas/química , Ligantes , Dados de Sequência Molecular , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
A new fluoro-Wang resin is presented which facilitates solid-phase reaction monitoring using 19F NMR. The resin is easily synthesized and amenable to scale-up. The method described herein compliments single-bead FT-IR and 13C NMR techniques. This method allows monitoring of solid-phase reactions even if the resin bound intermediate is unstable to the cleavage conditions. In addition, this is a useful tool to study reaction kinetics on the solid phase.
RESUMO
A series of competitive, nonpeptide bradykinin receptor antagonists based on an alpha-amino acid scaffold have been developed and biologically characterized. The lead compound in the series, WIN 64338, demonstrates competitive inhibition of bradykinin-mediated functional responses through B2 receptors in a variety of tissues and species. WIN64338 is a specific for the bradykinin B2 receptor; it is inactive at both the B1 and B2 kinin receptors. In conscious guinea pigs, WIN 64338 inhibits kinin-mediated bronchoconstriction but does not attenuate a similar response to acetylcholine. A series of WIN 64338 analogues display a well-defined structure-activity relationship, strongly suggesting binding in a specific manner to the B2 receptor. Structure-activity data suggest that a hydrophobic binding pocket that prefers large aromatic groups in a specific conformational orientation exists in the receptor ligand binding domain. This class of nonpeptide bradykinin receptor antagonists may lead to the design of other compounds with enhanced receptor affinity and optimal in vivo biological activity.
Assuntos
Antagonistas dos Receptores da Bradicinina , Naftalenos/farmacologia , Compostos Organofosforados/farmacologia , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Relação Estrutura-AtividadeRESUMO
The isolated rabbit jugular and human umbilical veins respond to bradykinin (BK) by contractions that are mediated by the BK B2 type receptors. In this report, the pharmacology of recently developed BK B2 receptor antagonists is assessed by using these preparations. The nonpeptide kinin antagonist WIN 64338 (phosphonium, [[4-[[2-[[bis(cyclohexylamino)methylene]amino]- 3-(2-naphthalenyl)-1-oxopropyl]amino]phenyl]methyl]tributyl chloride monohydrochloride) demonstrates competitive and surmountable antagonism of BK in both the jugular and the umbilical veins (pA2 values of 6.14 and 5.99, respectively). WIN 64338 shows selectivity in its antagonist action as it does not inhibit the effect of various other contractile agents in either of the preparations. HOE-140 (D-Arg[hydroxyproline3,beta-thienylalanine5, D-Tic7, octahydroindol-2-yl-carbonyl residue8]-BK), a "second generation" peptide antagonist of BK, behaves as an insurmountable and irreversible antagonist in the rabbit jugular vein, but appears to be competitive in the umbilical vein (pA2 = 8.2). In the jugular vein, [L-Tic7]HOE-140 is an insurmountable antagonist about 2000-fold less potent than HOE-140; the L-Tic7 isomer demonstrates no significant antagonist activity on the umbilical vein at 30 microM. This study confirms that WIN 64338 behaves as a competitive and selective kinin antagonist of the BK B2 type receptors. The pharmacological profile of the L-Tic7 analog of HOE-140 may provide useful information in discerning the molecular interaction of noncompetitive BK antagonists with their receptors.
Assuntos
Antagonistas dos Receptores da Bradicinina , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Naftalenos/farmacologia , Compostos Organofosforados/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Bradicinina/antagonistas & inibidores , Feminino , Humanos , Técnicas In Vitro , Veias Jugulares/efeitos dos fármacos , Veias Jugulares/fisiologia , Masculino , Coelhos , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/fisiologiaRESUMO
A focused library (4 x 14) prepared from 4-aminopyridine and 4-, 5-, and 6-azoindole templates was synthesized using 14 polymer supported 4-amido-2,3,5,6-tetrafluorophenyl (TFP) sulfonate esters inputs. Several compounds were identified as factor Xa inhibitors (IC50< or =0.1 microM) helping to establish the SAR among these four series of azarene pyrrolidinones.
Assuntos
Anticoagulantes/síntese química , Anticoagulantes/farmacologia , Técnicas de Química Combinatória , Inibidores do Fator Xa , Pirrolidinonas/química , Anticoagulantes/metabolismo , Pirrolidinonas/metabolismo , Pirrolidinonas/farmacologia , Relação Estrutura-AtividadeRESUMO
A Lead Discovery Library of piperazine-2-carboxamide derivatives was produced for general screening. This paper discloses two novel solid phase synthetic routes used to produce 15,000 single compounds via the Irori directed sorting technique. Computational methods such as reagent clustering and library profiling were used to maximize reagent diversity and optimize pharmacokinetic parameters. The results of a four center pharmacophore analysis revealed the added diversity gained by using two independent synthetic routes.
Assuntos
Técnicas de Química Combinatória , Piperazinas/síntese químicaRESUMO
D-Arg0[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (HOE-140) is a potent (Ki = 0.11 nM) inhibitor of [3H]bradykinin binding to bradykinin B2 receptors found on human IMR-90 fetal lung fibroblasts. During the synthesis of this compound, we isolated and unambiguously identified the L-Tic7 stereoisomer (WIN 65365), which exhibits a 2000-fold lower binding affinity (Ki = 130 nM) than HOE-140 to the bradykinin receptor. A similar decrease in potency is observed for WIN 65365 inhibition of bradykinin-stimulated 45Ca2+ efflux from IMR-90 cells. Both HOE-140 and WIN 65365 appear to be competitive antagonists at the IMR-90 bradykinin receptor. This is the first documentation of bradykinin binding and functional antagonist activity by a bradykinin peptide analogue with an L amino acid replacing Pro7. In an attempt to rationalize the differences in binding affinities of HOE-140 and WIN 65365, a conformational analysis of the peptides was undertaken using annealed molecular dynamics (AMD). Conformational analysis of HOE-140 reveals a strong preference for the formation of a type II' beta-turn in the carboxy-terminal region. Analogous modeling of WIN 65365 reveals that its conformation is strikingly different from HOE-140 in that the four carboxy-terminal residues of WIN 65365 do not form a beta-turn. These differences in low-energy conformations between the two peptides may lead to a better understanding of the molecular interaction of antagonists with the bradykinin receptor.
Assuntos
Bradicinina/análogos & derivados , Bradicinina/antagonistas & inibidores , Receptores da Bradicinina/metabolismo , Sequência de Aminoácidos , Bradicinina/síntese química , Bradicinina/química , Cálcio/metabolismo , Linhagem Celular , Humanos , Técnicas In Vitro , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Estereoisomerismo , Relação Estrutura-Atividade , TermodinâmicaRESUMO
A new tetrafluorophenol activated resin that facilitates the use of 19F NMR to quantitate loading is presented. This new resin provides a useful tool for acylation, and a novel activated polymeric sulfonate ester to generate sulfonamides. This activated resin reacts with a wide scope of N-nucleophiles including primary and secondary amines, and anilines. This new activated resin methodology provides a powerful tool for pure single-compound library synthesis.
RESUMO
Synthesis of an arylsulfone hydroxamate lead optimization library is presented. Biological activity of representative examples is given to demonstrate the value of this approach for lead optimization.
Assuntos
Ácidos Hidroxâmicos/síntese química , Sulfonas/química , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/farmacologia , Inibidores de Metaloproteinases de Matriz , Relação Estrutura-AtividadeRESUMO
We report the synthesis and in vitro biological activity of the nonpeptide bradykinin receptor antagonist WIN 64338, [[4-[[2-[[bis(cyclohexylamino)methylene]amino]-3-(2- naphthyl)-1-oxopropyl]amino]phenyl]methyl]tributylphosphonium chloride monohydrochloride. WIN 64338 inhibits [3H]-bradykinin binding to the bradykinin B2 receptor on human IMR-90 cells with a binding inhibition constant (Ki) of 64 +/- 8 nM and demonstrates competitive inhibition of bradykinin-stimulated 45Ca2+ efflux from IMR-90 cells (pA2 = 7.1). The antagonist inhibits bradykinin-mediated guinea pig ileum contractility (pA2 = 8.2) and has significantly weaker activity against acetylcholine-induced contractility in the same preparation. WIN 64338 is not active in a rabbit aorta bradykinin B1 receptor assay, demonstrating that it is a selective bradykinin B2 receptor antagonist. The compound inhibits [3H]quinuclidinyl benzilate binding to the rat brain muscarinic receptor (Ki = 350 nM) but is 25- to 100-fold more selective for the bradykinin receptor compared with other receptors against which it has been tested. Synthesis of WIN 64338 has provided a nonpeptide competitive bradykinin B2 antagonist active in both bradykinin radioligand binding and functional assays.