Immobilization of Ag(0) nanoparticles on quaternary ammonium functionalized polyacrylonitrile fiber as a highly active catalyst for 4-nitrophenol reduction

Ag(0) nanoparticles were immobilized on various pyridine salt, imidazole salt and quaternary ammonium functionalized polyacrylonitrile fibers (PANFs) to prepare Ag(0)-immobilized fiber catalysts.

Fine tuning of pyridinium-functionalized dibenzo[a,c]phenazine near-infrared AIE fluorescent biosensors for the detection of lipopolysaccharide, bacterial imaging and photodynamic antibacterial therapy

A series of NIR fluorescent probes of dibenzophenazine pyridine salt with different alkyl chain were developed for the detection of LPS. BD2C with ethyl chain exhibited a significant improvement of the singlet oxygen yield and antibacterial property.

Reaction of amines with the bisulphite addition compound of 5-Amino-5-deoxy-D-xylose: Conversion to piperidine derivatives

The bisulphite addition compound (1) of 5-amino-5-deoxy-D-xylose reacted with cyclohexylamine to form the acyclic derivative (11). With ammonia, benzylamine, morpholine, and piperidine, corresponding salts (IV) of the piperidine derivative D-ido(gluco)-3,4,5-trihydroxy-2-sulphopiperidine (VIII), were isolated. Removal of the amine yielded the crystalline bisulphite addition compound (VIII). Acetylation in the presence of pyridine of the different amine salts (11, IV) and of (VIII) gave an identical acetate (VII), l-acetyl-D-ido(gluco)-3,4,5-triacetoxy-2-sulphopiperidine, isolated as the pyridine salt. Deacetylation of (VII) with barium methoxide gave the barium salt (IX). Oxidation of (IX) with sodium periodate liberated one mole of formic acid, confirming the presence of a six-membered ring containing nitrogen. The significance of these results in the inhibition of non-enzymic browning by sulphur dioxide is discussed.

THE REACTION OF PYRIDINE AND PICOLINES WITH 2-BROMO-2-NITRO-1,3-INDANDIONE

2-Bromo-2-nitro-1,3-indandione (I) reacts with pyridine in a complex reaction at ordinary temperature. The main reaction products are 2-nitro-1,3-indandione pyridine salt, pyridine hydrobromide, phthalic acid, and a black tar consisting of oxidized polymer of pyridine hydrobromide. The reaction of (I) with picolines follows the same route.The electronic theory has been applied to demonstrate the structure of 2-nitro-1,3-indandione (II). In water solutions or in salts (II) exists in the form of an anion which is stabilized by several resonating structures.