ABSTRACT
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.
Subject(s)
Cobalt/chemistry , Hydrogen/chemistry , Peptides/chemistry , Silicon/chemistry , Oxidation-Reduction , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform InfraredABSTRACT
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.
ABSTRACT
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.
Subject(s)
Antineoplastic Agents/pharmacology , Quinolines/pharmacology , Cell Line, Tumor , Drug Screening Assays, Antitumor , HumansABSTRACT
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.
Subject(s)
Antineoplastic Agents/chemical synthesis , Camptothecin/analogs & derivatives , Camptothecin/chemical synthesis , DNA/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Camptothecin/chemistry , Camptothecin/pharmacology , Cattle , Cell Survival/drug effects , DNA/metabolism , DNA Footprinting , Drug Screening Assays, Antitumor , Humans , Inhibitory Concentration 50 , Male , Prostatic Neoplasms/pathology , Structure-Activity Relationship , Thymus Gland/metabolism , Tumor Cells, CulturedABSTRACT
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.
