发明人李文辉,刘建华,徐明华. "一种的合成方法" [P]. 中国发明专利, 专利号 CN 113971895 A, 授权公告日 2021-11-14.
发明人孙丽萍,马晓峰,徐明华. "Method for the Synthesis of Methyl 1-ethyl-2-imino-5-oxo-2,5-dihydro-1H-dipyrido[1,2-a:2',3'-d]pyrimidine-3-carboxylate" [P]. 中国发明专利, 专利号 CN 113488348 A, 授权公告日 2021-07-18.
发明人罗永刚,杨光,沈红梅. "A Process for Preparing High-Purity Methyl 1-ethyl-2-imino-5-oxo-2,5-dihydro-1H-dipyrido[1,2-a:2',3'-d]pyrimidine-3-carboxylate" [P]. 中国发明专利, 专利号 CN 114204564 B, 授权公告日 2017-11-05.
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