OPC-8212 is obtained through the piperazine ring formation method from bis(beta-bromoethyl)amine hydrobromide and 6-amino-3,4-dihydro-2(1H)-quinolinone (V) to give (VI). (V) is synthesized using the ring closure reaction of p-acetylamino-beta-ethoxyacryloanilide (II). p-Acetylaminoaniline (I) is converted to (II) by treatment with beta-ethoxyacryloyl chloride and afterwards cyclized in the presence of sulfuric acid to give 6-acetylamino-2-(1H)-quinolinone (III). Hydrogenation of (III) over 10% palladium on charcoal gives 6-acetylamino-3,4-dihydro-2(1H)-quinolinone (IV). Hydrolysis of (IV) gives 6-amino-3,4-dihydro-2(1H)-quinolinone (V). OPC-8212 is obtained by adding 3,4-dimethoxybenzyl chloride (VII) to (VI).