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发明人刘建华,杨光,林芳. "A Process for Preparing High-Purity Ethyl (R)-5-(difluoromethyl)-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine-2-carboxylate" [P]. 中国发明专利, 专利号 CN 112232363 B, 授权公告日 2015-11-16.
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