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AssigneeDsm IP Assets B.V.
InventorsDennis Heemskerk, Anja Gerarda Margaretha Hogenboom, Carlos Enrique Lenhardt, Harold Monro Moody, Theodorus Johannes Godfried Maria Van Dooren
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The present invention describes a process for preparing cephradine, said process comprising reacting 7-aminodesacetoxy cephalosporanic acid (7-ADCA) with D-dihydrophenylglycine in activated form (DHa) in the presence of an enzyme in a reaction mixture to form cephradine, resulting in a conversion of 7-ADCA into cephradine of at least 70%, wherein the concentration D-dihydrophenylglycine (DH) in the reaction mixture is below 2 wt.%, wherein the conversion of 7-ADCA into cephradine & equals; (nCEF/n7-ADCA)*100%, wherein nCEF=quantity of cephradine formed (in mole); and n7-ADCA=total quantity of 7-ADCA added to reaction mixture (in mole). The invention also describes a process for the preparation of cephradine hydrate characterised in that the process comprises: —reacting 7-amino acid desacetoxy cephalosporanic acid (7-ADCA) with DHa in the presence of an enzyme in a reaction mixture to form cephradine; —preparing an aqueous solution comprising at least part of the cephradine; and crystallising the cephradine from said aqueous solution. The invention further describes cephradine hydrate obtainable by a process according to invention. The invention also describes cephradine hydrate with an absorbance at 450 nm of below 0.050.
Process for preparing cephradine, said process comprising reacting 7-aminodesacetoxy cephalosporanic acid (7-ADCA) with D-dihydrophenylglycine in activated form (DHa) in the presence of an enzyme in a reaction mixture to form cephradine, resulting in a conversion of 7-ADCA into cephradine of at least 70%, wherein the concentration D-dihydrophenylglycine (DH) in the reaction mixture is below 2 wt. % throughout the reaction;
Process for preparing cephradine hydrate crystals with a water content between 3% and 6% by weight, characterized in that the process comprises crystallizing cephradine from an aqueous solution to form cephradine hydrate, wherein said crystallizing is carried out at a temperature of between 45 and 60° C.
Dependencies are inferred from the claim text.