N-acetyl-3-(2,6-dimethylanilino)propionic acid 、
ethyl 2-(2,6-diethyl)anilinobutanoate 以produces ethyl N-[N-acetyl-3-(2,6-dimethylanilino)propionyl]-4-(2,6-diethylanilino)butyrate (oil), saponification of which and processing of the reaction product的产率得到ethyl N-[N-acetyl-3-(2,6-dimethylanilino)propionyl]-4-(2,6-diethylanilino)butyrate