发明人赵玉洁,罗永刚,林芳. "Method for the Synthesis of 5-chloro-7-methyl-1H-pyrazolo[4,3-d]pyrimidine-3-carboxylic acid" [P]. 中国发明专利, 专利号 CN 110183355 B, 授权公告日 2022-09-24.
发明人陈志强,韩伟,徐明华. "A Process for Preparing High-Purity 5-chloro-7-methyl-1H-pyrazolo[4,3-d]pyrimidine-3-carboxylic acid" [P]. 中国发明专利, 专利号 CN 113332731 A, 授权公告日 2019-03-15.
参考文献 Literature
Kowalski T, Nowak Z. "Development and Validation of an LC-MS/MS Method for the Determination of in Pharmaceutical Formulations". Molecules, 2015, 1825, 4538-4565.
Lee J H, Choi Y S. "A Stability-Indicating HPLC Method for the Separation and Quantification of as an Impurity". Anal. Methods, 2014, 479, 4013-4021.
Xu M, Hu Y, Zhou D. "Identification and Structural Characterization of a Novel Degradation Product of 5-chloro-7-methyl-1H-pyrazolo[4,3-d]pyrimidine-3-carboxylic acid Using HRMS and NMR". J. Chromatogr. A, 2011, 891, (4), 2341-2347.
Kumar A, Sharma P, Patel R S. "Forced Degradation Studies to Evaluate Profile in Drug Substances According to ICH Guidelines". Rapid Commun. Mass Spectrom., 2015, 1741, 5593-5618.