RESUMO
The synthesis and Delta F508-CFTR corrector activity of a 148-member methylbithiazole-based library are reported. Synthetic routes were devised and optimized to generate methylbithiazole analogs in four steps. Corrector potency and efficacy were assayed using epithelial cells expressing human Delta F508-CFTR. These structure-activity data establish that the bithiazole substructure plays a critical function; eight novel methylbithiazole correctors were identified with low micromolar potencies.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Tiazóis/química , Tiazóis/farmacologia , Aminação , Linhagem Celular , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Epiteliais/efeitos dos fármacos , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese químicaRESUMO
4-Amino-4-deoxychorismate synthase (ADCS) catalyzes the first step in the conversion of chorismate into p-aminobenzoate, which is incorporated into folic acid. We aim to discover compounds that inhibit ADCS and serve as leads for a new class of antimicrobial compounds. This report presents (1) synthesis of a mass-tag encoded library based on a "staged" design, (2) massively parallel fluorescence-based on-bead screening, (3) rapid structural identification of hits, and (4) full kinetic analysis of ADCS. All inhibitors are competitive against chorismate and Mg(2+). The most potent ADCS inhibitor identified has a K(i) of 360 microM. We show that the combinatorial diversity elements add substantial binding affinity by interacting with residues outside of but proximal to the active site. The methods presented here constitute a paradigm for inhibitor discovery through active site targeting, enabled by rapid library synthesis, facile massively parallel screening, and straightforward hit identification.
Assuntos
Acetatos/síntese química , Anti-Infecciosos/síntese química , Benzoatos/síntese química , Carbono-Nitrogênio Ligases/antagonistas & inibidores , Peptídeos/síntese química , Fenoxiacetatos/síntese química , Acetatos/química , Anti-Infecciosos/química , Benzoatos/química , Sítios de Ligação , Carbono-Nitrogênio Ligases/química , Cátions Bivalentes , Ácido Corísmico/química , Técnicas de Química Combinatória , Desenho de Fármacos , Corantes Fluorescentes , Éteres de Hidroxibenzoatos , Cinética , Magnésio/química , Biblioteca de Peptídeos , Peptídeos/química , Fenoxiacetatos/química , Ligação Proteica , Resinas Sintéticas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , TransaminasesRESUMO
A novel one-step synthesis of 2,3-dihydro-1H-quinazolin-4-ones from 2-nitrobenzamides is reported. These reactions are mediated by stannous chloride in 0.02 M methanolic or ethanolic HCl solution and proceed in good yields.
Assuntos
Álcoois/química , Benzamidas/química , Quinazolinas/síntese química , Compostos de Estanho/química , Espectroscopia de Ressonância Magnética , Modelos MolecularesRESUMO
A new calcium-selective ionophore N,N-dioctyl-3alpha,12alpha-bis(N-heptyl-N-methylcarbamoyl-methoxyacetamidoacetoxy)-5beta-cholan-24-amide (denoted as BACA), was synthesized, and its potentiometric performance has been evaluated in comparison with that of the best known calcium-selective neutral carriers, ETH 129 and ETH 1001. The 1H NMR spectra of BACA titrated with Ca(SCN)2 suggest that BACA forms a 1:1 complex, tweezing a calcium ion between the two parallel diamide groups substituted on a rigid bile acid frame. The calcium-selective membrane based on BACA was less selective to calcium (log K(Ca2+ j)POT = -4.2, -4.2, -4.6, and -4.8, respectively, for j = Mg2+, Li+, Na+, and K+) than those based on ETH 129 (log K(Ca2+ j)POT = -4.4, -4.3, -5.4, and -5.4, respectively, in the same order) and ETH 1001 (log K(Ca2+ j)POT = -4.4, -4.4, -5.4, and -5.4), implying that BACA forms a weaker calcium complex than the other two ETH compounds. In our experimental conditions, potentiometrically determined complex formation constants of calcium-selective neutral carriers (log beta(Ca2+ L)) were 15.2, 14.0, and 8.6 for ETH 129, ETH 1001, and BACA, respectively. A slightly reduced calcium selectivity of BACA, however, affects the anionic interference-free calcium-selective membrane; the BACA-based membrane exhibits a Nernstian response up to 10(-1) M Ca2+ in the presence of lipophilic anions (e.g., SCN-, ClO4-, salicylate, and I-) and anionic surfactant, whereas the ETH 129- and ETH 1001-based ones suffer from serious anionic interference showing a curvature or leveled off response over about 10(-4) M. It was demonstrated that such a trade off does not affect the analytical performance of BACA-based electrode in most applications, including clinical analysis.