Morphotropism and “Quasi-Isostructurality” in the Three High Z′ Concomitant Polymorphs of Efinaconazole
journal contributionposted on 27.05.2020, 21:43 by Rafel Prohens, Rafael Barbas, Mercè Font-Bardia
The crystal structures of the three efinaconazole anhydrous forms have been solved by single-crystal X-ray diffraction showing a very rare case of nearly isostructural polymorphism. The analysis of their crystal structures revealed that forms I and III are “quasi-isostructural” polymorphs and are morphotropically related to form II. The identical conformational and supramolecular environment can explain the concomitant polymorphism phenomenon observed for this important active pharmaceutical ingredient.