A novel two-dimensional NMR pulse sequence, H2BC, for long-range correlation of 1H and 13C nuclei is presented. The experiment has several attractive features compared to the widely used HMBC experiment, for example, (a) typically strong enhancement of correlations over two bonds while suppressing those over more bonds, that is, resolving ambiguities in standard HMBC spectra and showing two-bon...

A simple amphiphilic surfactant containing a mono-quaternary ammonium head group (N-methylpiperidine) is effective in imparting substantial mesoporosity during synthesis of SSZ-13 and ZSM-5 zeolites. Highly mesoporous SSZ-13 prepared in this manner shows greatly improved catalytic performance in the methanol-to-olefins reaction compared to bulk SSZ-13.

1,1-Dimethyl-3-oxo-1,4-diazepan-1-ium chloride (1) and 1,1-dimethyl-1-carboxymethyl-3-aminopropyl ammonium hydrochloride (2) have been obtained by the reactions of 1,1-dimethyl-1,3-propylenediamine with ethyl chloroacetate and chloroacetic acid, respectively. The products have been characterized by FTIR, Raman and NMR spectroscopy. B3LYP calculations have also been carried out. The screening co...

This work describes the synthesis of a series of quaternary ammonium salts and the assessment of their in vitro antileishmanial activity and cytotoxicity. A preliminary discussion on a structure-activity relationship of the compounds is also included. Three series of quaternary ammonium salts were prepared: (i) halomethylated quaternary ammonium salts (series I); (ii) non-halogenated quaternary...

Salmonella serovars sampled from meat products in Southern Spain (Andalucía) during the period 2002-2007 were analyzed in this study. The serovars most frequently detected (in order) were Typhimurium, Enteritidis, Derby, Anatum and Rissen. Isolates (n = 43) were tested for sensitivity to biocides, including the quaternary ammonium compounds benzalkonium chloride (BC), cetrimide (CT) and hexadec...

Tertiary amines 3-(dialkylamino)-2-hydroxypropyl 4-[(alkoxycarbonyl)amino]benzoates and their quaternary ammonium salts were synthesized. The final step of synthesis of quaternary ammonium salts was carried out by microwave-assisted synthesis. Software-calculated data provided the background needed to compare fifteen new resulting compounds by their physicochemical properties. The acid dissocia...

Quaternary ammonium salts are frequently used as antibacterial agent that disrupts cell membrane through the binding of their ammonium cations to anionic sites in the outer layer tissue of bacteria. This article describes the synthesis of quaternary ammonium salt-type antibacterial agents with a phosphate group that strongly binds to hydroxyapatite and bromide ion as counterion. Evaluation of t...