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发明人唐晓军,刘建华,冯建国. "A Process for Preparing High-Purity Ethyl 5-(hydroxymethyl)-5-methyl-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine-2-carboxylate" [P]. 中国发明专利, 专利号 CN 117071965 B, 授权公告日 2016-01-05.
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