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Information × Registration Number 0221U105841, 0120U104907 , R & D reports Title Study of polymorphic transitions of molecular crystals for the needs of the pharmaceutical industry. popup.stage_title Head Shyshkina Svitlana V., Registration Date 06-09-2021 Organization State Scientific Institution Scientific and Technological Complex" Institute of Single Crystals "of the National Academy of Sciences of Ukraine popup.description2  The polymorphic transition of a benzothiasine derivative (analogue of pyroxicam) from a monoclinic structure in triclinic one for four weeks after grinding is studied. The monoclinic polymorph crystallizes from a more volatile solvent, has a layered structure and exhibits high anti-diuretic and analgesic activity. Polymorphic transition occurs solely as a result of orientational factors and leads to loss of biological activity. For 3- (1- (tert-butoxycarbonyl) azetidine-3-yl) -1,2-oxazol-4-carboxylic acid, a polymorphic transition as a result of grinding occurs due to conformational and orientational factors. The prerequisite for the transition is the high conformational flexibility of the molecule, low barriers of nitrogen inversion and rotation of the substituents around the single bonds, as well as the ability of the carboxyl group to form two types of supramolecular synthons. Polymorphic modifications are constructed from molecular (metastable structure) or dimeric (stable structure) building units. Product Description popup.authors popup.nrat_date 2021-09-06 Close