a rapid, specific and accurate proton quantitative nuclear magnetic resonance spectroscopic (1h qnmr) and also a reversed phase derivatization hplc method have been developed to quantify a toxic, uv-visible inactive and non-volatile impurity n,n-dimethylamine hydrochloride (dma∙hcl) in metformin hydrochloride (mf∙hcl), an active pharmaceutical ingradient. the method is based on proton quantitat...

A simple, rapid, accurate and precise analytical method for determination of secondary and tertiary amines in hydrochloride salt form of drug substances in non-aqueous medium, which does not require any derivatization, was developed by headspace gas chromatography. Dimethylamine hydrochloride and triethylamine hydrochloride were analyzed in metformin hydrochloride. The sample was dissolved in a...

Within a total residence time of 9 min, the sodium salt of ciprofloxacin was prepared from simple building blocks via a linear sequence of six chemical reactions in five flow reactors. Sequential offline acidifications and filtrations afforded ciprofloxacin and ciprofloxacin hydrochloride. The overall yield of the eight-step sequence was 60 %. No separation of intermediates was required through...

The formation of /V-nitroso compounds in mouse stom ach from equimolar doses of sodium nitrite and secondary amines or alkylurea derivatives given simultaneously by a stomach tube was estimated by measuring the mutagenic activity of the compounds in the i.p. host-mediated assay with the use of Salmonella typhimurium TA1950 as genetic indicator system. A mutagenic response in the bacteria was fo...

1. A mono-oxygenase, which oxidizes trimethylamine and other tertiary amines bearing methyl or ethyl groups, was partially purified sixfold from Pseudomonas aminovorans grown on trimethylamine as sole carbon source. 2. The preferred electron donor was NADPH. The enzyme had a pH optimum of 8.0-9.4 for trimethylamine oxidation, and 8.8-9.2 for dimethylamine oxidation. 3. The oxidation product of ...

A number of new charge-neutral zwitterionic tris(methimazolyl)borate ligands have been synthesized, either by substitution of the dimethylamine group in the adduct (dimethylamine)tris(methimazolyl)borane (1) or by insertion into its B-N(dimethylamine) bond by an unsaturated Lewis base. Two new anionic ligands, (thiocyanato)tris(methimazolyl)borate and (cyano)tris(methimazolyl)borate, have also ...

We have studied the hydration of sulfuric acid – ammonia and sulfuric acid – dimethylamine clusters using quantum chemistry. We calculated the formation energies and thermodynamics for clusters of one ammonia or one dimethylamine molecule together with 1–2 sulfuric acid and 0–5 water molecules. The results indicate that dimethylamine enhances the addition of sulfuric acid to the clusters much m...

spectrophotometric and electrochemical studies were successfully used in quantitative analysis of amitriptyline hydrochloride (ath) and nortriptyline hydrochloride (nth). conductometric titration were carried out in equeous solution using iodide and dopamine and serotonine as titrant. two new methods using spectrophotometry are dascribed for the determination of (ath) and (nth) with potassium b...

Abstract Carbon quantum dots (CQD) were prepared from three different precursors and by bottom-up synthesis methods: classical pyrolysis of citric acid (CAP), microwave irradiation glucose (GM), hydrothermal treatment glucosamine hydrochloride (GAH). CQD further functionalized using various nitrogen-containing compounds: 6-aminohexanoic acid, 1,6-diaminohexane, N-octylamine, dimethylamine, tryp...