The invention discloses a synthesis method of
cefminox sodium, which comprises the following steps: completely dissolving methoxycephalosporin (7-MAC) and
dichloromethane in a reaction flask (1), and adding
pyridine and
carbon tetrachloride; after complete reaction, adding a
saturated aqueous solution of
sodium chloride for extracting and layering, and performing vacuum concentration on a bottom-phase organic phase; adding
dichloromethane and
ethanol into a reaction flask (2), and introducing
hydrogen chloride gas; after complete reaction, adding the concentrated liquid in the reaction flask (1) into the reaction flask (2); after complete reaction, adding a mixed
solvent for extracting and layering; performing liquid separation on the organic phase by use of the
saturated aqueous solution of
sodium chloride, and keeping the bottom-phase organic phase; adding D-
cysteine into the organic phase, adjusting the pH value of the solution to 6.0-6.5, and keeping the temperature at 20-25 DEG C; after sufficient reaction, feeding
ethanol, and performing sufficient
crystal precipitation and
vacuum drying to obtain
cefminox sodium. According to the method, the reaction process causes
low toxicity, the operation is safe, the quality and yield of the product are increased, and the
crystal form of the product is good and easy to dry, thus the method is suitable for popularization and application in
mass production.