[Determination of a dimethylaniline mixture in the intermediate products for the production of semisynthetic penicillins].

A gas-chromatographic method for determination fo the content of dimethylaniline (DMA) in 6-aminopenicillanic acid, a semi-product for production of semi-synthetic antibiotics, was elaborated. The chloroform extracts of DMA from the alkaline solutions of the preparation were analysed in a gas chromatograph with a flame-ionization detector on a stainless steel column 2 m long and the inner diameter of 2 mm filled with 10 per cent OV-17 on chromosorb W-HMDS at a temperature of 112 degrees C. The minimum detectable amount of DMA was 5.10(-9) g. The assay error was +/- 5.35 per cent. The method may be used for the assay of other semi-synthetic antibiotics.