Denotivir (CAS NO.: 51287-57-1), with its systematic name of 5-Benzamido-4'-chloro-3-methyl-4-isothiazolecarboxanilide, could be produced through many synthetic methods.

Following are some of the synthesis routes:
1) 3-Methyl-5-aminoisothiazole-4-carboxylic acid (I) reacts with benzoyl chloride in acetone solution and in the presence of pyridine to produce the benzamide (II), which by reaction with SOCl₂ is converted to the lactam (III). Next, the reaction of lactam (III) with p-chloroaniline in anhydrous ethanol produces the p-chlorophenylamide (vratizolin).
2) 3-Methyl-5-benzoylamino-4-isothiazolecarboxylic acid (II) reacts with chloroformic ethyl ester to afford the mixed anhydride, which, when heated with p-chloroanitine in anhydrous ethanol forms title compound. Vratizolin is also a product of the reaction of the acid (II) with p-chloroaniline in the presence of dicyclohexylcarbodiimide.