the kinetics of iodination of the phenol and substituted phenols using pyridiniumiodochloride in methanol has been studied under varying conditions. the rates show first orderkinetics each in pyridinium iodochloride and phenols. the rates of reactions are measured atdifferent temperature and activation parameters for all phenols computed. hammett plot is foundto be valid and the corrletion betw...

The cycloaddition of pyridinium ylides with alkynes was investigated under mild conditions. A series of 13 pyridinium salts was prepared by alkylation of 4-substituted pyridines. Their reactivity with propiolic ester or amide in various reaction conditions (different temperatures, solvents, added bases) was studied, and 11 indolizines, with three points of structural variation, were, thus, isol...

The role of pyridinium cations in electrochemistry has been believed known for decades, and their radical forms have been proposed as key intermediates in modern photoelectrocatalytic CO(2) reduction processes. Using first-principles density functional theory and continuum solvation models, we have calculated acidity constants for pyridinium cations and their corresponding pyridinyl radicals, a...

objective(s): the aim of this study was to synthesize triangular gold nanoparticles, and then to evaluate their capability for inhibition of candida albicans secreted aspartyl proteinase 2(sap2).materials and methods: to synthesize the nanoparticles, hydrogen tetrachloroaurate and hexadecyl trimethyl ammonium bromide were incubated in presence of sn(iv) meso-tetra(n-methyl-4-pyridyl) porphine t...

Novel, double-chained pyridinium compounds have been developed that display highly efficient DNA transfection properties. The transfection efficiency of several of these compounds is enhanced by an order of magnitude, when compared with the transfection efficiency accomplished with the widely used cationic lipid system, lipofectin. Most importantly, the pyridinium compounds were found to be ess...

Objective(s): The aim of this study was to synthesize triangular gold nanoparticles, and then to evaluate their capability for inhibition of Candida albicans secreted aspartyl proteinase 2(Sap2).Materials and Methods: To synthesize the nanoparticles, hydrogen tetrachloroaurate and hexadecyl trimethyl ammonium bromide were incubated in presence of Sn(IV) meso-tetra(N-methyl-4-pyridyl) porphine t...

isatin, n-methyl isatin and n-benzylisatin were smoothly monobrominated in the 5-position by treatment with pyridinium bromochromate (pbc) in acetic acid medium. in the similar conditions indigo underwent bromination and oxidation to give 5-bromoisatin in high yield.

The product,ion of bacterial growth inhibitors derived from acidic vitamins by the substitution of a sulfonic acid group for the carboxyl group of the vitamin is now well known. Thus sulfanilamide, the sulfur analogue of p-aminobenzoic acid (I), pyridine-3-sulfonic acid, the analogue of nicotinic acid (2), and thiopanic acid, the analogue of pantothenic acid (3-5), have been shown to prevent gr...