The notoriously non-selective aryl-diazonium surface-functionnalization turned selective in the presence of electron-deficient heterocycle. electro-activation probe allowed rapid and nearly quantitative liberation covalently tethered ligands.

Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental results showed that the measured effectiveness Mlog(1/MRC50) does not depend on the number of azo groups or the ones...

the synthesis and properties of new monoazo dyes derived from the diazonium salts of paminobenzoic acid, 3-trifluoromethyl aniline , 4-trifluoromethyl aniline are considered .theprepared compounds were characterized by uv-visible , ft-ir and h nmr spectroscopictechniques . the effect of varying solvent upon the absorption ability of p-amino benzoic acidcoupled with 4,4 —diethyl aniline , anilin...

Previous reports have claimed Adriamycin to be cytotoxic to cultured tumor cells when the drug is covalently immobilized on a solid support, thus suggesting a cell surface mechanism of action for the drug. Although these previous reports attempted to rule out released drug or endocytosis of drug-support particles as alternative explanations for the observed cytotoxicity, a more thorough analysi...

Build-up of enzyme–polyelectrolyte multilayer onto glassy carbon (GC) surfaces by electrostatic self-assembling method has been investigated. In order to functionalize GC surface by a starting negatively charged layer, two approaches have been carried out: (i) covalent linkage of phenyl acetic acid through electroreduction of 4-phenylacetic diazonium salt (GCA surface), and (ii) formation of a ...

A new preparation method of polymer dyes was developed to improve both the grafting degree of the azo dyes onto O-carboxymethyl chitosan (OMCS) and the water solubility of prepared polymer dyes. Firstly, the coupling compound of two azo edible colorants, sunset yellow (SY) and allura red (AR), was grafted onto OMCS, and then coupled with their diazonium salt. The chemical structure of prepared ...

The reaction of cyclopentanone with cyanoacetylhydrazine gave 2-cyano-2-cyclopentylideneacetohydrazide (1). Treatment of compound 1 with elemental sulphur in the presence of triethylamine afforded 2-amino-5,6-dihydro- -4H-cyclopenta[b]thiophene-3-carbohydrazide (2), which in-turn formed the corresponding intermediate diazonium salt. The latter was coupled with either ethyl cyanoacetate or ethyl...

A very simple, sensitive, fairly selective and rapid spectrophotometric method for the determination of trace amounts of nitrite has been described. This method is based on the diazotized intramolecular coupling of electrophilic diazonium cation with the phenolic group of 4-amino-5-hydroxynaphthalene-2,7-disulphonic acid monosodium salt (AHNDMS) in a phosphate buffer solution of pH 7.5. The cyc...

The properties of Si(111) surfaces grafted with benzene derivatives were investigated using ultraviolet photoemission spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS). The investigated materials were nitro-, bromo-, and methoxybenzene layers (-C(6)H(4)-X, with X = NO(2), Br, O-CH(3)) deposited from diazonium salt solutions in a potentiostatic electrochemical process. The UPS spectr...

At least three groups of polypeptides of the inner membrane of rat liver mitochondria have been shown to be exposed to the exterior surface by several techniques: lactoperoxidase-catalyzed iodination of mitochondria and inner membrane/matrix vesicles (mitoplasts), reaction of mitochondria and mitoplasts with the membrane-impermeable diazonium salt of sulfanilic acid, and controlled proteolysis ...