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发明人郭海燕,罗永刚,黄志刚. "A Process for Preparing High-Purity Ethyl 4-oxo-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate" [P]. 中国发明专利, 专利号 CN 116278605 B, 授权公告日 2022-07-26.
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