Björnsson E, Nowak P, Schröder R. "一种的合成方法" [P]. European Patent, EP 3107497 A1, 2022-04-04.
发明人李文辉,高志强,罗永刚. "Method for the Synthesis of Ethyl 4,6-bis(difluoromethyl)-1-methyl-1H-pyrazolo[3,4-b]pyridine-3-carboxylate" [P]. 中国发明专利, 专利号 CN 111673440 A, 授权公告日 2018-11-04.
发明人王建平,冯建国,韩伟. "A Process for Preparing High-Purity Ethyl 4,6-bis(difluoromethyl)-1-methyl-1H-pyrazolo[3,4-b]pyridine-3-carboxylate" [P]. 中国发明专利, 专利号 CN 109607157 A, 授权公告日 2025-11-24.
参考文献 Literature
Brown R C, Davis S M. "Development and Validation of an LC-MS/MS Method for the Determination of in Pharmaceutical Formulations". Chemosphere, 2019, 224, 1228-1231.
Kumar A, Sharma P, Patel R S. "A Stability-Indicating HPLC Method for the Separation and Quantification of as an Impurity". Rapid Commun. Mass Spectrom., 2012, 942, 9847-9867.
Yamamoto K, Tanaka H, Suzuki T. "Identification and Structural Characterization of a Novel Degradation Product of Ethyl 4,6-bis(difluoromethyl)-1-methyl-1H-pyrazolo[3,4-b]pyridine-3-carboxylate Using HRMS and NMR". Chromatographia, 2010, 1174, (12), 5012-5022.