Patent ID: 10125122

Abstract:
The invention relates to a method of synthesizing methyl (Z)-3-[[4-[methyl[2-(4-methyl-1-piperazinyl)acetyl]amino]phenyl] amino]phenylmethylene)-oxindole-6-carboxylate of formula (1), known under the generic name of intedanib or nintedanib. The present method comprises a) a reaction of methyl oxindole-6-carboxylate with acetic anhydride at a temperature of 130-140° C., providing methyl 1-acetyl-oxindole-6-carboxylate; b) a reaction of methyl 1-acetyl-oxindole-6-carboxylate of with trimethyl orthobenzoate and acetic anhydride in the presence of toluene, providing methyl (E)-1-acetyl-3-(methoxyphenylmethylene)-oxindole-6-carboxylate; c) a reaction (E)-1-acetyl-3-(methoxyphenylmethylene)-oxindole-6-carboxylate with N-(4-aminophenyl)-N,4-dimethyl-1-piperazine acetamide and subsequently with an alkali hydroxide or alkali alkoxide in methanol or ethanol without isolation of the intermediate, providing methyl (Z)-3-[[4-[methyl[2-(4-methyl-1-piperazinyl)acetyl]amino]phenyl] amino]phenylmethylene)-oxindole-6-carboxylate, wherein the reaction is conducted at a temperature of 50 to 100° C. (1).