RESUMO
In fragment-based screening, the choice of the best suited fragment hit among the detected hits is crucial for success. In our study, a kinase lead compound was fragmented, the hinge-binding motif extracted as a core fragment, and a minilibrary of five similar compounds with fragment-like properties was selected from our proprietary compound database. The structures of five fragments in complex with transforming growth factor ß receptor type 1 kinase domain were determined by X-ray crystallography. Three different binding modes of the fragments are observed that depend on the position and the type of the substitution at the core fragment. The influence of different substituents on the preferred fragment pose was analyzed by various computational approaches. We postulate that the replacement of water molecules leads to the different binding modes.
Assuntos
Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/química , Estrutura Terciária de Proteína , Bibliotecas de Moléculas Pequenas/química , Cristalografia por Raios X , Desenho de Fármacos , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/química , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologiaRESUMO
Chemically diverse fragment hits of focal adhesion kinase (FAK) were discovered by surface plasmon resonance (SPR) screening of our in-house fragment library. Site specific binding of the primary hits was confirmed in a competition setup using a high-affinity ATP-site inhibitor of FAK. Protein crystallography revealed the binding mode of 41 out of 48 selected fragment hits within the ATP-site. Structural comparison of the fragment binding modes with a DFG-out inhibitor of FAK initiated first synthetic follow-up optimization leading to improved binding affinity.
Assuntos
Descoberta de Drogas , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Indóis/química , Indóis/farmacologia , Fragmentos de Peptídeos/farmacologia , Bibliotecas de Moléculas Pequenas , Sulfonamidas/química , Sulfonamidas/farmacologia , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Fragmentos de Peptídeos/genética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Solubilidade , Ressonância de Plasmônio de SuperfícieRESUMO
The dual serotonin (5-HT) re-uptake inhibitor and 5-HT(1A) receptor agonist vilazodone was found to increase central serotonin levels in rat brain. In the course of structural modifications of vilazodone 3-[4-[4-(2-oxo-2H-1-benzopyran-6-yl)-1-piperazinyl]-butyl]-1H-indole-5-carbonitrile 8i and its fluorine analogue 6-[4-[4-(5-fluor-3-indolyl)-butyl]-1-piperazinyl]-2H-1-benzopyran-2-one have been identified. These unsubstituted chromenones are equally potent at the 5-HT(1A) receptor and 5-HT transporter. The implementation of nitrogen functionalities in position 3 of the chromenones resulted in compounds acting as agonists at the 5-HT(1A) receptor and as 5-HT re-uptake inhibitors like vilazodone. Ex vivo 5-HT re-uptake inhibition and in vitro 5-HT agonism were determined in the PCA- and GTPgammaS-assay, respectively. The potential of these chromenones to increase central 5-HT levels was measured in microdialysis studies and especially the derivatives 3-[4-[4-(3-amino-2-oxo-2H-chromen-6-yl)-piperazin-1-yl]-butyl]-1H-indole-5-carbonitrile 8f, ethyl (6-[4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl]-2-oxo-2H-chromen-3-yl)-carbamate 8h and N-(6-[4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl]-2-oxo-2H-chromen-3-yl)-acetamide 8k give rise to rapid development of increased serotonin levels in rat brain cortex, lasting longer than 3h.
Assuntos
Benzofuranos/farmacologia , Indóis/farmacologia , Piperazinas/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Agonistas do Receptor 5-HT1 de Serotonina , Agonistas do Receptor de Serotonina/farmacologia , Animais , Benzofuranos/química , Benzofuranos/metabolismo , Benzopiranos/química , Benzopiranos/metabolismo , Benzopiranos/farmacologia , Butilaminas/química , Butilaminas/metabolismo , Butilaminas/farmacologia , Combinação de Medicamentos , Indóis/química , Indóis/metabolismo , Masculino , Estrutura Molecular , Piperazinas/química , Piperazinas/metabolismo , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/química , Agonistas do Receptor de Serotonina/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/química , Inibidores Seletivos de Recaptação de Serotonina/metabolismo , Cloridrato de VilazodonaRESUMO
Integrin adhesion receptors frequently recognize a core amino acid sequence, Arg-Gly-Asp, in their target ligands. Inhibitors with the ability to inhibit one or a small subset of such RGD-dependent integrins have been invaluable in defining their biological function. Here, we have characterized low molecular weight inhibitors for their ability to specifically inhibit alphav(beta)6 integrin, a fibronectin/tenascin receptor. As of yet, no nonpeptidic inhibitor of alphav(beta)6 was known. New peptidomimetic and nonpeptidic compounds were examined in isolated integrin binding assays and in cell adhesion assays for their ability to block alphav(beta)6, alphav(beta)3, alphav(beta)5, and alphalIb(beta)3 integrins. The compounds are based on an aromatically substituted beta amino acid or glutaric acid derivative as an acidic center and an aminopyridyl or guanidyl residue as a basic mimetic. We found several classes of inhibitors with different selectivities, especially mono- or biselectivity on the alpha(v)-integrins alphav(beta)6 and alphav(beta)3, and nanomolar activity. Furthermore, nearly all compounds are inactive on alphaIIb(beta)3. Compound 11 is the first specific, peptidomimetic inhibitor of the alphav(beta)6 integrin receptor.
