RESUMO
While fluorescent-based methods are generally used to detect the immobilization and the interactions of biomolecules to solid supports, recent studies have shown their limitations in the case of silicon surfaces. As an alternative, we investigated the synthesis of peptides labeled with a metal transition complex and their subsequent immobilization to the silicon surfaces. The feasibility of using such probes has been explored by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). By starting with hydrogen-terminated or oxidized silicon surfaces, we functionalized those surfaces with semicarbazide groups and showed the site-specific linkage of glyoxylyl peptides labeled with a Co2(CO)6 moiety.
Assuntos
Cobalto/química , Hidrogênio/química , Peptídeos/química , Silício/química , Oxirredução , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Despite the importance of the isocyanate group in chemistry, very few examples of isocyanate-modified silicas have been reported, and all of the strategies described so far led to partial or total hydrolysis or condensation of the isocyanate group. By synthesizing trichlorosilane isocyanate as the coupling reagent, we show that oxidized silicon wafers are successfully modified with the isocyanate group. Our method is achieved in mild conditions, at low temperature, without side-reactions and allows the formation of a self-assembled monolayer (SAM) of isocyanates. The isocyanate group then offers a flexible way to further functionalize silica substrates with different nucleophiles, due to its high and specific reactivity.
RESUMO
An assessment of structure-activity relationships associated with the new benzo[5,6]pyrrolizino[1,2-b]quinoline system displaying potent in vitro cytotoxic activity against the MCF7 cell line is described.
Assuntos
Antineoplásicos/farmacologia , Quinolinas/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , HumanosRESUMO
Camptothecin consists of a lactone E-ring adjacent to a tetracyclic A-D ring planar chromophore which are essential for topoisomerase I inhibition and DNA interaction, respectively. The A-D ring system can be exploited to develop DNA-binding molecules. Indolizino[1,2-b]quinoline derivatives substituted with a piperidinoethyloxy side chain on the A-ring and an aminomethyl function on the D one were synthesized and their DNA-binding properties and in vitro cytotoxicity investigated.
Assuntos
Antineoplásicos/síntese química , Camptotecina/análogos & derivados , Camptotecina/síntese química , DNA/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Camptotecina/química , Camptotecina/farmacologia , Bovinos , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Pegada de DNA , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Masculino , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade , Timo/metabolismo , Células Tumorais CultivadasRESUMO
Camptothecin consists of a lactone E ring adjacent to tetracyclic A-D rings of a planar chromophore, which are essential for topoisomerase I inhibition and DNA interaction. The A-D rings can be exploited to develop DNA-sequence-reading molecules. Indolizino[1,2-b]quinoline derivatives substituted with a piperidinoethyloxy side chain and an aminomethyl function on rings A and D, respectively, were synthesized, and their DNA binding and formaldehyde-mediated bonding properties were investigated.