Smith, Mark G. published the artcileNovel crystal forms of 4-aminoantipyrine and its derivatives: Co-crystallizing a reluctant molecule, Quality Control of 86-48-6, the publication is Journal of Molecular Structure (2019), 307-313, database is CAplus.
To the best of our knowledge, the first co-crystallization of the pharmaceutical ingredient 4-aminoantipyrine is reported with 2-aminobenzoic acid as the co-former, and the method used for its supramol. synthesis is discussed. Two mol. salts of 4-aminoantipyrine, as well as two co-crystals of a derivative of 4-aminoantipyrine were also synthesized. The complexes discussed show that careful application of synthon theory, choice of solvent and consideration of the pKa difference between 4-aminoantipyrine and the co-former are required to successfully co-crystallize this reactive mol. In summary, the co-former must be chosen so that its functional group forms a robust heterosynthon with the reactive mol. The presence of polar solvents or large pKa differences between 4-aminoantipyrine and its potential co-crystallizer favors salt formation, whereas a non-polar solvent and a small pKa difference is required for the co-crystallization of 4-aminoantipyrine.
Journal of Molecular Structure published new progress about 86-48-6. 86-48-6 belongs to alcohols-buliding-blocks, auxiliary class Organic Pigment,Natural product, name is 1-Hydroxy-2-naphthoic acid, and the molecular formula is C18H28N2O7, Quality Control of 86-48-6.
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