Compounds of formula (I): in which: R¹ is alkyl or alkenyl R² and R³ are hydrogen, alkyl, alkenyl, cycloalkyl, aralkyl, aryl, or aryl fused to cycloalkyl R⁴ is hydrogen, alkyl, alkanoyl, alkenoyl, arylcarbonyl, alkoxycarbonyl, tetrahydropyranyl, tetrahydrothiopyranyl, tetrahydrothienyl, tetrahydrofuryl, a group of formula -SiRaRbRc, in which Ra, Rb and Rc are alkyl or aryl, alkoxymethyl, (alkoxyalkoxy)methyl, haloalkoxymethyl, aralkyl, aryl or alkanoyloxymethoxycarbonyl R⁵ is carboxy or a group of formula -CONR⁸R⁹, in which R⁸ and R⁹ are hydrogen atoms or alkyl, or R⁸ and R⁹ together form alkylene R⁶ is hydrogen, alkyl, alkoxy or halogen R⁷ is carboxy or tetrazol-5-yl and pharmaceutically acceptable salts and esters thereof have hypotensive activity and can be used for the treatment and prophylaxis of hypertension. They may be prepared, interalia, by reacting a biphenylmethyl compound with an imidazole compound.
