Nitrosation of quaternary ammonium compounds in vivo in the Wistar rat.

The respiration of rat-liver slices in the presence of some aliphatic amines, hydroxyamines and quaternary ammonium salts.

Induction of contact dermatitis in guinea pigs by quaternary ammonium compounds: the mechanism of antigen formation.

Eight quaternary ammonium compounds were tested for their ability to induce contact dermatitis in guinea pigs by using a modified Freund's complete adjuvant test together with the guinea pig maximization test. Only two quaternary ammonium salts of the eight tested could be designated as strong allergens. These two active substances were shown to be capable of stable association with membrane li...

Effect of Quaternary Ammonium Carboxymethylchitosan on Release Rate In-vitro of Aspirin Sustained-release Matrix Tablets

The aim of this study was to develop a derivative of chitosan as pharmaceutical excipient used in sustained-release matrix tablets of poorly soluble drugs. A water-soluble quaternary ammonium carboxymethylchitosan was synthesized by a two-step reaction with carboxymethylchitosan (CMCTS), decylalkyl dimethyl ammonium and epichlorohydrin. The elemental analysis showed that the target product with...

Altered neurochemical levels in the rat brain following chronic nicotine treatment.

Converging evidence shows that neurochemical systems are crucial mediators of nicotine dependence. Our present study evaluates the effect of 3-month chronic nicotine treatment on the levels of multiple quaternary ammonium compounds as well as glutamate and gamma aminobutyric acid in the rat prefrontal cortex, dorsal striatum and hypothalamus. We observed a marked decrease of acetylcholine level...

preparation of 3, 4-dihydropyrimidin-2(1H)-ones using quaternary ammonium- treated clay in water

In this study, a variety of 3, 4-dihydropyrimidin-2(1H)-ones derivatives were synthesized via three-component Biginelli reaction. The quaternary ammonium- treated clay -catalyzed process proved to be simple, efficient, and environmentally friendly.