Studies on the Quality of Pharmaceutical Preparations. IV. Gas Chromatographic Determination of Cinchophen and Other Components in Drugs

Methods are described for the gas-liquid chromatographic estimation of cinchophen, sodium salicylate, aminopyrine, and isopropylantipyrine in drugs. Dioctylphthalate was used as internal standard. Before chromatography sodium salicylate was converted to an O-capryl ester with capryl chloride, and to an O-methyl ester with diazomethane, and cinchophen was converted to the same O-methyl ester as sodium salicylate. Aminopyrine and isopropylantipyrine was not affected by the above conditions for conversion to the O-derivatives. Cinchophen and sodium salicylate, aminopyrine and isopropylantipyrine were determined simultaneously and rapidly without any additional separatory operations.