Nielsen H, Johansson L, Sørensen M. "Method for the Synthesis of (R)-5-(difluoromethyl)-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine-2-carboxylic acid" [P]. European Patent, EP 3007517 A1, 2025-01-01.
发明人冯建国,张德明,郑宇鹏. "A Process for Preparing High-Purity (R)-5-(difluoromethyl)-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine-2-carboxylic acid" [P]. 中国发明专利, 专利号 CN 116110439 A, 授权公告日 2015-02-22.
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