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Interactive Molecular Model Assembly with 3D Printing
Published on: August 13, 2020
The disordered structure of sparsentan: energy calculations for competing chain conformations
Thomas Gelbrich1, Kristaps Saršüns1, Doris E Braun1
1Christian Doppler Laboratory for Advanced Crystal Engineering Strategies in Drug Development, Innrain 52c, Innsbruck, 6020, Austria.
Abstract:
The crystalline form of sparsentan (SST) (systematic name: 2-{4-[(2-butyl-4-oxo-1,3-diazaspiro[4.4]non-1-en-3-yl)methyl]-2-(ethoxymethyl)phenyl}-N-(4,5-dimethyl-1,2-oxazol-3-yl)benzenesulfonamide), C32H40N4O5S, was produced and characterized using single-crystal and powder X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and IR spectroscopy. The SST molecule displays positional disorder in three different sections. Viability tests of alternative disorder models involved the calculation of energetic contributions to analyse each possible molecular conformation within its crystal environment and identify the energetically most favourable conformations in the lattice.
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