| abstract |
PROCEDURE FOR PREPARING CEPHALOSPORINS OF FORMULA (I), WHERE A IS PHENYL 4-HYDROXYPHENYL, CYCLOHEXYL OR OTHERS; D HYDROGEN, HYDROXY, ACETOXY AND OTHERS; R HYDROGEN, METHYL, CYCLOPROPYL OR OTHERS, AND E HYDROGEN OR AN EASILY REMOVABLE PROTECTING GROUP "IN VITRO". A COMPOUND D FORMULA (II) IS REACTED AT A TEMPERATURE OF -120 TO -10 C WITH AN ALKALI METAL METHYLATE, IN THE PRESENCE OF EXCESS METHANOL, AND IN AN INERT SOLVENT MEDIUM. THE REACTION MIXTURE IS TREATED WITH A HALOHENATION AGENT, SUCH AS HALOGENS, N-HALOGENOIMIDES, ETC. ONCE THE REACTION IS COMPLETED, THE EXCESS HALOGENATION AGENT IS REMOVED BY MEANS OF A REDUCING AGENT. OF APPLICATION AS ANTIBIOTICS AGENTS |