[Potential cardiotonics. 15. Crystal modifications of 3-cyano-2-morpholino-5-(4-pyridinyl)pyridine (AWD 122-14)]

The preparation and X-ray crystallographic characterisation of 10 polymorphic or pseudo-polymorphic forms of the novel cardiotonic AWD 122-14 are described. Thermic transformations of some polymorphic forms into the alpha-form was proved by thermogravimetric analysis and powder diffraction pattern. In dissolution behaviour no significant differences were found between the crystalline modifications but with regard to galenic processing compact alpha-, gamma- and epsilon-forms show advantages.