Patel M V, Mueller T, Brown S R. "Method for the Synthesis of 4-Oxo-4H-pyrano[3,2-b]benzofuran-2-carboxylic acid" [P]. US Patent, US 10381788 B2, 2021-12-13.
Kowalski A, Schröder R, Björnsson E. "A Process for Preparing High-Purity 4-Oxo-4H-pyrano[3,2-b]benzofuran-2-carboxylic acid" [P]. European Patent, EP 3116480 A1, 2018-05-12.
参考文献 Literature
Lee J H, Choi Y S. "Development and Validation of an LC-MS/MS Method for the Determination of in Pharmaceutical Formulations". Anal. Chim. Acta, 2017, 2274, (5), 8605-8608.
Wang L, Li J, Zhang H. "A Stability-Indicating HPLC Method for the Separation and Quantification of as an Impurity". Phytochemistry, 2011, 855, (12), 5366-5382.
Smith J A, Johnson M B. "Identification and Structural Characterization of a Novel Degradation Product of 4-Oxo-4H-pyrano[3,2-b]benzofuran-2-carboxylic acid Using HRMS and NMR". Anal. Methods, 2014, 1395, (10), 4913-4921.