A process for the preparation of cephalosporins

摘要

The present invention relates to a process for the preparation of cephalosporins, particularly for the preparation of 7-( alpha -hydroxyacylamino)-3-(1-sulfoalkyl-tetrazol-5-yl-thiomethyl)-3-cephem- 4-carboxylic acids and the salts thereof. The method provides the direct recovery, by freeze-drying, of the active ingredient in a pure form ready for the pharmaceutical use. The method of the invention is based on reverse osmosis techniques.