Tetrazole derivatives and drugs

A compound of the formula [I] ##STR4## or a pharmacologically acceptable salt thereof wherein A is --(O)m--(CH(R.sup.4))n--, wherein R.sup.4 is hydrogen or alkyl of 1 to 4 carbon atoms, and m and n are each 0 or 1;

• B is oxygen or --S(O)p--, wherein p is 0 to 2;
• R.sup.1 is hydrogen, alkyl of 1 to 4 carbon atoms, halogen, haloalkyl of 1 to 4 carbon atoms substituted by one to three halogen moieties or hydroxy;
• R.sup.2 is alkyl of 1 to 10 carbon atoms, alkenyl of 2 to 10 carbon atoms, alkyl of 1 to 6 carbon atoms substituted by phenyl, alkyl of 1 or 2 carbon atoms substituted by naphthyl or alkyl of 1 to 10 carbon atoms substituted by COOR.sup.3, hydroxy, CON(R.sup.6)R.sup.7, quinolin-2-yl, 7-chloroquinolin-2-yl or 1H-tetrazol-5-yl, wherein R.sup.3 is hydrogen, alkyl of 1 to 6 carbon atoms or alkyl of 1 to 6 carbon atoms substituted by CON(R.sup.6)R.sup.7, and R.sup.6 and R.sup.7 are the same or different and each is hydrogen or alkyl of 1 to 4 carbon atoms;
• R.sup.8 is hydrogen, alkoxy of 1 to 4 carbon atoms or halogen;
• R.sup.9 is hydrogen, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, acyloxy of 2 to 5 carbon atoms, halogen, nitro or hydroxy;
• and
• R.sup.10 is hydrogen or alkyl of 1 to 4 carbon atoms.