Lobachevsky University scientists discover the phenomenon of polymorphism in the atomic structure of the methylprednisolone aceponate crystal
Scientists at Lobachevsky University (UNN) in Nizhny Novgorod are studying physico-chemical properties of steroid hormone crystals. Steroid hormones are a group of physiologically active substances that regulate the processes of vital activity in animals and humans. These include, for example, sex hormones, corticosteroids, etc. In particular, corticosteroids are a subclass of steroid hormones that are produced exclusively by the adrenal cortex. Corticosteroids are characterized by their glucocorticoid or mineralocorticoid activity.
UNN researchers have discovered the phenomenon of polymorphism in the atomic structure of the methylprednisolone aceponate crystal. In 2017, a paper was published in the Journal of Molecular Structure reporting the results of their studies of the corticosteroid hormone methylprednisolone aceponate. Nizhny Novgorod scientists managed to synthesize a single crystal of this substance, which was of a sufficient size for X-ray diffraction studies. As a result, a three-dimensional model of the atomic structure of methylprednisolone aceponate at different temperatures was obtained for the first time.
In particular, it was found that at a temperature of 131 K (-142°C), the methylprednisolone aceponate crystal experiences a second-order phase transition. It is manifested in the fact that with a decrease in temperature, chaotically located methyl groups are ordered and exhibit a strict spatial periodicity. In this case, one of the parameters of the unit cell increases by a factor of 3 compared with the high-temperature phase.
In-depth study of physicochemical properties of steroid hormone crystals is important for the synthesis of new medicines. It is also of great practical value for the modern pharmaceutical industry: to create a new medicine, not only an appropriate active substance is required, but also an effective method for storing it.