Chromatographic Separation of Isomers of Tribenzylgermanium Nitrile Derivatives using Chemically Bonded Aryl Stationary Phases

Journal of Liquid Chromatography & Related Technologies

et al. 2015

Self Cite

This article presents the results deriving from research made on the development of optimal conditions for chromatographic separation and determination of such compounds as: quinine, quinidine, and acetylquinidine. The compounds subject to analysis are used in the treatment of malaria. Three stationary phases were used in the examination: octadecyl, which is perceived by analysts as the standard one, and two aryl phases (benzylpropyl and naphthylpropyl). For the mobile phases, the following compounds were adopted: methanol, acetonitrile, and a mixture of acetonitrile=water=formic acid. The best separation of quinine, quinidine, and acetylquinidine was observed in the naphthylpropyl column with the application of methanol as the mobile phase. The coefficients of separation of these compounds with the flow of methanol of 0.8 mL min À1 were 1.17 and 1.14, respectively. However, no proper separation of the compounds was observed in the octadecyl column, regardless of the mobile form applied.

Section: Resultsmentioning

confidence: 99%

Determination of Quinine and its Derivatives with High-Performance Liquid Chromatography

Kluska

Komasińska

Journal of Liquid Chromatography & Related Technologies

et al. 2015

Self Cite

“…Repeatedly it was shown that this type of phase is, first of all, designed for determination of p electron containing compounds. [12][13][14][15][16] In the chromatographic process carried out with a participation of such stationary phase and analyzed substances, interactions of p -p type predominate. Owing to increased selectivity in numerous determinations, separation was improved and retention times shortened.…”

Section: Resultsmentioning

confidence: 99%

Chromatography of Biologically Active Chlorides of (E)-N-o-(m- or p-)chlorobenzyl-γ-azastilbenols-2′(3′ or 4′)

Journal of Liquid Chromatography & Related Technologies

Pypowski³

et al. 2008

Self Cite

results of investigations concerning optimization of chromatographic separation and determination of (E)-N-o-(m-or p-)chlorobenzyl-c-azastilbenols-2 0 (3 0 or 4 0 ) are presented. Analyzed isomers show antimicrobial activity. In the investigation, were considered three stationary phases (octadecyl, octyl, and naphthylpropyl), two mobile phases (acetonitrile, dichloromethane), and various intensities of flow. The best selectivity (a 1 ¼ 1.34, a 2 ¼ 1.47) was obtained using naphthylpropyl column and 100% acetonitrile, as the mobile phase. An application of octadecyl phase, recommended by numerous analysts as standard, did not yield satisfactory results.

“…These types of phases is, first of all, designed to determine p electron containing compounds. [14][15][16][17] In the chromatographic process carried out with a participation of such stationary phases and analyzed substances, interactions of p-p types are predominating. Owing to increased selectivity, in numerous determinations separation was improved and retention times were shorter.…”

Section: Resultsmentioning

confidence: 99%

Separation of Biologically Active Isomers of Nitroazastilbenes by the HPLC Technique

Journal of Liquid Chromatography & Related Technologies

Pypowski³

et al. 2008

Self Cite

Optimum conditions for chromatographic separation of bromides of (E)-N o-, m-, and p-nitrobenzyl-4 0 -hydroxy-3 0 -methoxystilbazole-4 are presented. This work was a continuation of an earlier investigation, which was necessary because of difficulties when standard (octadecyl) phases had been applied. Analyzed isomers show antimicrobial activity. In the investigation were considered three aryl stationary phases ( phenylbutyl, naphthylpropyl, and Hypercarb), two mobile phases (acetonitrile, dichloromethane), and various intensities of flow. The best selectivity (a 1 ¼ 1.74, a 2 ¼ 1.22) was obtained using the naphthylpropyl column and 100% acetonitrile as the mobile phase. An application of the octadecyl phase, recommended by numerous analysts as the standard, allowed only to observe an existence of two compounds, but did not yield satisfactory results.