Losartan potassium, a non-peptide agent for the treatment of arterial hypertension.

In the title compound, potassium 2-butyl-4-chloro-1-[[2'-(5-tetrazolido)biphenyl-4-yl]methyl]-1H-imidazol-5-ylmethanol, K(+) x C(22)H(22)ClN(6)O(-), the imidazole and tetrazole rings are at angles of 85.0 (2) and 51.8 (1) degrees, respectively, to the phenyl rings to which they are attached, while the dihedral angle between the latter two rings is 46.7 (1) degrees. The coordination sphere of the metal cation consists of six tetrazoyl N atoms, the methanol O atom and the pi cloud of one of the phenyl rings. These interactions determine the formation of columns of molecular anions that lie parallel to the b axis, while hydrogen bonding contributes to intercolumnar cohesion. Far from the centre of the columns, the hydrocarbon chain is immersed in a hydrophobic environment.