Nielsen H, Nowak P, Schröder R. "一种6-cyclopropyl-1-(4-fluorophenyl)-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid的合成方法" [P]. European Patent, EP 3043768 A1, 2021-02-26.
发明人赵玉洁,陈志强,杨光. "Method for the Synthesis of 6-cyclopropyl-1-(4-fluorophenyl)-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid" [P]. 中国发明专利, 专利号 CN 110997836 B, 授权公告日 2015-06-21.
Lefèvre J P, Rossi M, Martínez F. "A Process for Preparing High-Purity 6-cyclopropyl-1-(4-fluorophenyl)-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid" [P]. European Patent, EP 3403476 A1, 2022-06-21.
参考文献 Literature
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Brown R C, Davis S M. "A Stability-Indicating HPLC Method for the Separation and Quantification of 6-cyclopropyl-1-(4-fluorophenyl)-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid as an Impurity". J. Nat. Prod., 2014, 905, 7304-7322.
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