摘要 |
Process for purifying 7-substituted aminodeacetoxycephalosporins through the use of filter membranes. A process for purification by ultrafiltration and/or nanofiltration with a cut-off for molecular weights over 10,000 Dalton and preferably over 2000 Dalton is described. For example cephalosporin-G of increased purity, represented by a 6-8% increase in the HPLC titre, with a reduction of 50% in absorbance, is obtained using this technique. The invention makes it possible for the purified products to be used directly in the synthesis of other antibiotic compounds without the need for intermediate isolation. <CHEM> R1 = H R2 = C6H5.CH2Co C6H5.0.CH2Co R3 = H, Na, K, ... |