4-tert-butoxycarbonylaminomethyl-2-(1-methoxycarbonyl-1-acetoxymethyl)aniline 、
(S)-9-chloro-5-carboxymethyl-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione 以to give 275 mg of the title compound (43.7%)的产率得到(5S)-9-Chloro-5-[p-tert-butoxycarbonylaminomethyl-o-(1-methoxycarbonyl-1-acetoxymethyl) phenylcarbamoylmethyl]-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione