Cefclidin (CAS NO.: 105239-91-6), with other name of Cefclidinum, could be produced through many synthetic methods.

Following is one of the synthesis routes:

[14C]-labeled potassium thiocyanate (I) is cyclized with 2-(N-chlorocarboxamidino)-2-(methoxyimino)acetic acid (II) in methanol in the presence of triethylamine to afford 2-(2-aminothiazol-4-yl)-2(Z)-(methoxyimino)acetic acid (III), which is treated with PCl₅ in dichloromethane, yielding the corresponding acyl chloride (IV). Finally, this compound is condensed with 7-amino-3-(4-carbamoylquinuclidinio-1-ylmethyl)-3-cephem-4-carboxylate (V) by means of sodium acetate in dichloromethane.