2-(4-ethoxycarbonylbutyl)-4-tert-butoxycarbonylaminomethylaniline 、
(S)-9-bromo-5-(carboxymethyl)-6,7-dihydro-1H,5H-pyrido<1,2,3-de>quinoxaline-2,3-dione 在
silica gel 作用下,
以
Ethyl acetate acetate 为溶剂,
以to give 365 mg of the title compound after silica gel column chromatography with 0.3% acetic acid/ethyl acetate (74%)的产率得到(S)-9-bromo-5-[p-tert-butoxycarbonylaminomethyl-o-(4-ethoxycarbonylbutyl)phenylcarbamoylmethyl]-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione