Crystal structure of azilsartan methyl ester ethyl acetate hemisolvate.

Abstract

The title compound, C26H22N4O5 (systematic name: methyl 2-eth­oxy-1-{4-[2-(5-oxo-4,5-di­hydro-1,2,4-oxa­diazol-3-yl)phenyl]benz­yl}-1H-1,3-benzo­diazole-7-carboxyl­ate ethyl acetate hemisolvate), was obtained via cyclization of methyl (Z)-2-eth­oxy-1-{(2′-(N′-hy­droxy­carbamimido­yl)-[1,1′-biphen­yl]-4-yl)meth­yl}-1H-benzo[d]imidazole-7-carboxyl­ate with diphen­yl carbonate. There are two independent mol­ecules (A and B) with different conformations and an ethyl acetate solvent mol­ecule in the asymmetric unit. In mol­ecule A, the dihedral angle between the benzene ring and its attached oxa­diazole ring is 59.36 (17); the dihedral angle between the benzene rings is 43.89 (15) and that between the benzene ring and its attached imidazole ring system is 80.06 (11)°. The corres­ponding dihedral angles in mol­ecule B are 58.45 (18), 50.73 (16) and 85.37 (10)°, respectively. The C—O—C—Cm (m = meth­yl) torsion angles for the eth­oxy side chains attached to the imidazole rings in mol­ecules A and B are 93.9 (3) and −174.6 (3)°, respectively. In the crystal, the components are linked by N—H⋯N and C—H⋯O hydrogen bonds, generating a three-dimensional network. Aromatic π–π stacking inter­actions [shortest centroid–centroid separation = 3.536 (3)Å] are also observed.