发明人罗永刚,唐晓军,钱学锋. "Method for the Synthesis of 4-(1-ethyl-1{H}-pyrazol-4-yl)-1-methyl-1{H}-pyrazolo[3,4-{b}]pyridine-3-carboxylic acid" [P]. 中国发明专利, 专利号 CN 114934860 B, 授权公告日 2017-09-25.
发明人冯建国,张德明,韩伟. "A Process for Preparing High-Purity 4-(1-ethyl-1{H}-pyrazol-4-yl)-1-methyl-1{H}-pyrazolo[3,4-{b}]pyridine-3-carboxylic acid" [P]. 中国发明专利, 专利号 CN 111394318 B, 授权公告日 2019-01-17.
参考文献 Literature
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Yang F, Sun W, Liu J. "Identification and Structural Characterization of a Novel Degradation Product of 4-(1-ethyl-1{H}-pyrazol-4-yl)-1-methyl-1{H}-pyrazolo[3,4-{b}]pyridine-3-carboxylic acid Using HRMS and NMR". J. Pharm. Biomed. Anal., 2023, 1870, 6927-6951.