Crystal structure and Hirshfeld surface analysis of the anhydrous form of the nucleoside analogue entecavir
Xiaojuan Wang1, Hai Jiang Xu1, Xue Dong Jia1
1Department of Phamacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, People's Republic of China.
Abstract:
The nucleoside analogue entecavir {systematic name: 2-amino-9-[(1S,3R,4S)-4-hydroxy-3-hydroxymethyl-2-methylenecyclopentyl]-1,9-dihydro-6H-purin-6-one}, C12H15N5O3, is an antihepatitis B virus drug that has been approved in the US, EU and several countries worldwide. We report here the single-crystal structure of the anhydrous form and compare it with that of the previously reported monohydrate form [Jiang & Liu (2009). Acta Cryst. E65, o2232]. Hirshfeld surface analysis has been employed to understand and visualize the subtle packing differences between the two crystalline forms. The results show that, compared to the previously reported hydrated form, the anhydrous crystal has significantly different intermolecular interactions and packing patterns.
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