The invention discloses a preparation method of high-purity
cefuroxime acid which is an intermediate for synthesizing second-generation cephalosporins
cefuroxime sodium and
cefuroxime axetil. The preparation method comprises the following steps: based on 7-aminocephalosporanic acid (7-ACA) as a
raw material, carrying out an N-
acylation reaction on the 7-ACA and furoyl
acetylcholine at the 7-position; at a low temperature, hydrolyzing 3-acetyl with a
sodium hydroxide solution, crystallizing, filtering and
drying so as to obtain the intermediate 3-deformamido cefuroxime acid (DCC); quantitatively adding the DCC in a
tetrahydrofuran solvent, dropwise adding
chlorosulfonyl isocyanate for a
nucleophilic addition reaction so as to generate chlorosulfonyl cefuroxime acid, and adding
purified water for
hydrolysis so as to prepare a cefuroxime acid reaction liquid; adding
sodium bicarbonate for salifying; removing by-reactant
lactone and other
unsaponifiable impurities in the reaction liquid with a
ternary compound extracting agent of
dichloromethane,
ethyl acetate and
tetrahydrofuran, layering, and adding
hydrochloric acid in a water phase for acidification; adding the
ternary compound extracting agent to extract and separate out the cefuroxime acid; and removing water-soluble impurities, crystallizing and filtering a distilled organic phase, and then
drying so as to obtain the high-purity cefuroxime acid with the purity of more than or equal to 99%.