Abstract: A process for preparation of cefuroxime axetil of formula (I) of at least 96% purity and substantially free of analogous ?2-isomer of formula (II) and other impurities. The process comprises reacting cefuroxime acid of formula (III) with (R,S)-1-acetoxyethyl bromide of formula (IV), and a Group I or II metal carbonate in the presence of a compound of formula (V), MmHnPqOr??(V) wherein M is Group I or II metal; m is 1, 2, 3; n is 0, 1, 2, or 4; q is 1 or 2; r is 4, 7 or 8; in the presence of a C1-4 alcohol and a polar tertiary amide solvent selected from N,N-dimethylacetamide, N,N-dimethylformamide, N,N-dimetheylpropionamide, N,N-diethylacetamide, N,N-diethylformamide and N,N-diethylpropionamide at a temperature ranging from about ?30 to +30° C. and subjecting the product thus obtained to a desired step of purification.

Abstract: A process for producing 4-bromo-2-oxyimino butyric acid, predominantly as the (Z)-isomer of formula (I), wherein R is hydrogen; a linear or branched C1-4 alkyl group; a linear or branched C1-4 alkyl group substituted by a carboxylic acid or an aryl group; a substituted or unsubstituted cyclic alkyl group of 3-6 carbon atoms or a substituted or unsubstituted aryl group. The product is produced by reacting bromine with a 2-(oxyimino)-3-oxo butyric acid derivative of formula (II) wherein R is as defined above and R1 is a tert-butyl group in presence of an organic solvent and in presence of a C1-4 alcohol and acetyl bromide at a temperature ranging from about ?15° C. to about +15° C. Bromine is used in a proportion of about 0.90 to about 1.35 moles per mole of compound (II), preferably 0.90 to 1.10 moles. The acetyl bromide is used in molar proportions of 0.9 to 2 moles per mole of compound (II), preferably 0.9 to 1.5 moles.

Abstract: An improved method for synthesis of cefuroxime axetil of formula (I) in high purity substantially free of the corresponding 2-cephem(&Dgr;2)-ester of formula (II) and other impurities. The compound produced is valuable as a prodrug ester of the corresponding cephalosporin-4-carboxylic acid derivative i. e. cefuroxime, particularly suitable for oral administration in various animal species and in man for treatment of infections caused by gram-positive and gram-negative bacteria.

Abstract: A process for producing 4-bromo-2-oxyimino butyric acid, predominantly as the (Z)-isomer of formula (I), 1