Tetrazole derivatives, and anti-ulcer composition containing the same

An anti-ulcer composition, which comprises as active ingredient an effective amount of a tetrazole derivative of the formula:

• ##STR40## wherein R.sup.1 is a lower alkyl, phenyl or a group of the formula:
• --S(O).sub.l --A--(X).sub.m --R.sup.3, and R.sup.2 is hydrogen, a lower alkyl, phenyl or a cycloalkyl when R.sup.1 is the group --S(O).sub.l --A--(X).sub.m --R.sup.3, or R.sup.2 is a group of the formula:
• --B--CO--R.sup.4 when R.sup.1 is a lower alkyl or phenyl;
• in said formula --S(O).sub.l --A--(X).sub.m --R.sup.3, X is --CO-- or S--(O).sub.n --, l and n are each 0, 1 or 2, m is 0 or 1, A is an alkylene having 1 to 8 carbon atoms, and R.sup.3 is a lower alkyl, a cycloalkyl, naphthyl, a group of the formula:
• ##STR41## (R.sup.5 is a lower alkyl), a phenyl(lower)alkyl which may have a halogen substituent on the phenyl ring, a phenyl which may have 1 to 3 substituents selected from the group consisting of a halogen, a lower alkyl, a lower alkoxy, a lower alkanoylamino, hydroxy, carboxy and amino, a heterocyclic group-substituted lower alkyl which may have a substituent selected from a lower alkyl and amino wherein the heterocyclic group is selected from pyridyl, furyl and thiazolyl, or a heterocyclic group containing 1 to 4 hetero atoms selected from nitrogen, oxygen and sulfur which may have 1 to 2 substituents selected from the group consisting of a lower alkyl, a halogen, carboxy, oxo, amino, a lower alkoxycarbonyl, a lower alkoxy, hydroxy, nitro, phenyl, a cycloalkyl and a lower alkylamino, wherein the heterocyclic group containing 1 to 4 hetero atoms is selected from thienyl, furyl, pyrrolyl, pyridyl, pyranyl, pyrimidyl, quinolyl, 1,2,3,4-tetrahydroquinolyl, imidazolyl, 1,3,4-thiadiazolyl, 1,3,4-oxadiazolyl, 1H-1,2,4-triazolyl, 4H-1,2,4-triazolyl, thiazolyl, 1,2,3,4-tetrazolyl, benzimidazolyl, quinazolyl, 2,4-dihydroquinazolyl, and 3H,4H-1,3,4-benzotriazepinyl, and when m is 0, R.sup.3 may also be a group of the formula:
• --NR.sup.6 R.sup.7 wherein R.sup.6 is hydrogen, a lower alkyl or a phenyl(lower)alkyl, and R.sup.7 is hydrogen, a lower alkyl, a group --CZ--NHR.sup.8 (Z is sulfur or an imino which may be substituted with a lower alkyl, and R.sup.8 is a lower alkyl or amino, a tetrazolyl which may have a lower alkyl substituent, or a group --CO--R.sup.9, wherein R.sup.9 is a lower alkyl, a phenyl which may have 1 to 3 lower alkoxy substituents, a cycloalkyl or a 5- or 6-membered unsaturated heterocyclic group containing one hetero atom selected from nitrogen and oxygen, said group being pyrrolidino, morpholino, 1-piperidinyl or 1-piperazinyl, or the R.sup.6 and R.sup.7 may combine together with the nitrogen atom to which they are joined to form a group ##STR42## in said formula --B--CO--R.sup.4, B is a lower alkylene, and R.sup.4 is a group of the formula:
• --NR.sup.10 R.sup.11 wherein R.sup.10 and R.sup.11 are the same or different and are each a lower alkyl (which may have a substituent selected from the group consisting of hydroxy, furyl, pyridyl, phenyl and a phenyl having 1 to 2 lower alkoxy substituents), a cycloalkyl (which may have a substituent selected from the group consisting of hydroxy or a lower alkoxy), a phenyl (which may have 1 to 2 substituents selected from the group consisting of a lower alkyl, a lower alkoxy, a halogen, nitro, carboxy and a lower alkylamino), or a thiazolyl, or the R.sup.10 and R.sup.11 may combine together with the nitrogen atom to which they are joined with or without being intervened with nitrogen or oxygen to form a 5- or 6-membered saturated heterocyclic group which may have a lower alkyl substituent, provided that when m is 0, R.sup.3 is not unsubstituted phenyl(lower)alkyl or unsubstituted phenyl, and provided that when B is methylene or dimethylmethylene (--C(CH.sub.3).sub.2 --), R.sup.4 excludes di-(lower)alkylamino and 1-piperidyl, or a pharmaceutically acceptable salt thereof in admixture with a carrier or diluent.