Synthesis, crystal structure and Hirshfeld surface analysis of the hydrated form of N’, N-(1,4-phenylenebis(methanylylidene) di(iso-nicotinic hydrazide)
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.
The title compound crystallises in the triclinic centrosymmetric space group P1̄ with an intriguing high number of crystallographically unique binary salt-like adducts (Z′ = 8) and a total number of ionic species (Z′′ = 16) in the asymmetric unit.
Crystal structure, characterization, Hirshfeld surface analysis and DFT studies of two [propane 3-bromo-1-(triphenyl phosphonium)] cations containing bromide (I) and tribromide (II) anions: The anion (II) as a new brominating agent for unsaturated compounds