METHOD FOR THE PURIFICATION AND ISOLATION OF WATER-SOLUBLE DERIVATIVES OF CEPHALOSPORIN C INDEXA

摘要

1368667 Producing cephalosporin C A compounds ELI LILLY & CO 22 Aug 1972 [23 Aug 1971] 39129/72 Heading C2A Cephalosporin C A compounds are prepared by reacting a crude cephalosporin C compound with a pyridine in the presence of thiocyanate ions in an aqueous medium at pH 6 to 7-5 for 4 to 6 hours at 55-70‹ C. Thereafter, a non-oxidizing mineral acid (e.g. HCl) is added to the reaction mixture with stirring to lower the pH to 2À8 to 3À5. Stirring is continued for 15 to 45 minutes, filterable material is separated, more acid is added to pH 1 to 1-5 and the precipitated cephalosporin-C A hydrothiocyanate salt is collected. The salt may be decomposed, e.g. by treatment with a liquid amine anion exchange resin, and purified by conventional methods, e.g. by scrubbing with chloroform and recrystallization.