Schröder R, Lee S K, Mueller T. "Method for the Synthesis of 6-[4-(difluoromethoxy)phenyl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid" [P]. US Patent, US 11269171 B2, 2019-12-04.
发明人唐晓军,高志强,王建平. "A Process for Preparing High-Purity 6-[4-(difluoromethoxy)phenyl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid" [P]. 中国发明专利, 专利号 CN 114733334 B, 授权公告日 2023-04-22.
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