Cephemcarboxylic acid esters of the general formula ##STR1## pharmaceutical preparations which are active against bacterial infections, which contain such cephem derivatives, a process for the preparation of the cephem derivatives and the pharmaceutical preparations, and also the use of the cephem derivatives for combating bacterial infections.
The invention relates to compositions in the form of cefixime-containing non-aqueous suspensions which have syrup-like characteristics, characterized in that they are free of thickening ancillary substances and contain a microfine powder of bulking agent with a particle size distribution with at least 80% by weight having a maximum diameter of 32 .mu.m and a maximum of 5% by weight having a diameter larger than 50 .mu.m, are very easily redispersible and are chemically stable.
Crystalline acid addition salts of diastereomerically pure 1-(2,2-dimethylpropionyloxy)ethyl 3-cephem-4-carboxylate The invention relates to crystalline acid addition salt of the two diastereomers of the 1-(2,2-dimethylpropionyloxy)ethyl 3-cephem-4-carboxylate of the general formula II ##STR1## in which X is the anion of a physiologically acceptable, mono- or polybasic, inorganic or organic acid and the group =N--OH is in the syn-position, pharmaceutical formulations which are active against bacterial infections and contain such cephem derivatives, processes for the preparation of the cephem derivatives and the use of the cephem derivatives for combating bacterial infections.
Enterally absorbable diastereomers of 1-(isopropoxycarbonyloxy)ethyl (6R,7R)-7-[2-(2-aminothiazol-4-yl)-2-(Z)-(methoxyimino)acetamido]-3-(metho xymethyl)-3-cephem-4-carboxylate of the formula I ##STR1## and their physiologically acceptable salts and also diastereomerically pure salts of the compounds of the formula II ##STR2## where HX is a mono- or polybasic acid and where X is an inorganic or organic physiologically acceptable anion, and a process for the preparation of these compounds of the formula I or II, which comprises first precipitating the more sparingly soluble diastereomer of the formula IV in the mixing together of 1 equivalent of a solution of the diastereomer mixture of the formula III with 0.2-2 equivalents of a solution of the acid component HY and separating it off by filtration, then precipitating the more readily soluble diastereomer of the formula IV from the filtration solution, it being possible for the acid component HY to be identical or different in the consecutive partial steps and any desired sequence of addition of different acid components HY being possible, and optionally further purifying the obtained salts by crystallization, are described.
The present invention relates to a process for the preparation of 7-amino-3-methoxymethylceph-3-em-4-carboxylic acid (I) from 7-amino-3-methoxymethylceph-3-em-4-carboxylic acid esters (II) or their salts by ester cleavage. The process comprises treating the compound II with formic acid, trifluoroacetic acid, methanesulfonic acid or trifluoromethanesulfonic acid or a mixture of two of these acids in each case.
