PURPOSE: To produce a cephalosporanic acid derivative useful as an intermediate having sufficient reactivity and high versatility in high yield wile suppressing the formation of by-products in the production of a cephalosporin-type antibiotic substance by reacting a specific compound with a halogenation agent in the presence of a base.
CONSTITUTION: This caphalosporanic acid derivative of formula II (X is halogen)(e.g. 7-phenoxyacetamido-3-chloromethyl-3-cephem-4-carboxylic acid) is produced by reacting a compound of formula I (R is an acyl, an alkoxycarbonyl or an aralkyloxycabonyl) with a halogenation agent in the presence of a base. preferably, a compound of formula III [M is alkali metal, alkaline earth metal or HNR1R2R3 (R1 to R3 are H, a 1-8C alkyl, a lower cycloalkyl); HNR1R2R3 may form aliphatic or aromatic 5 to 7-membered ring together with N atom] is used as the compound of formula I.
ISHII NAOYUKI
HAYASHI YOSHIHARU
