The title compound,
eprosartan mesylate {systematic name: 2-butyl-1-(4-carb-oxy-benz-yl)-5-[(E)-2-carb-oxy-3-(thio-phen-2-yl)prop-1-en-yl]-1H-imidazol-3-ium methane-sulfonate}, C(23)
H(25)N(2)O(4)S(+)·CH(3)O(3)S(-), one of the
angiotensin II-receptor antagonists, is effective in regulating
hypertension, induced or exacerbated by
angiotensin II, and in the treatment of
congestive heart failure,
renal failure and
glaucoma. In the
eprosartan residue, which appears in this crystal in the cationic imidazolium form, the
benzene ring plane is almost orthogonal to that of the
imidazole ring, making a dihedral angle of 87.89 (2)°. The thio-phene ring forms dihedral angles of 66.54 (2) and 67.12 (2)° with the
benzene and
imidazole rings, respectively. The imidazolium NH group and the H atom of the aromatic carboxyl group participate in hydrogen bonds with the the O atoms of the
anion, thus forming centrosymmetric aggregates made up of two
cations and two
anions each. The second carboxyl group further links the above-mentioned aggregates through a conventional centrosymmetric hydrogen-bonding motif into infinite chains along [011].