Azole derivatives and antiulcerative composition containing same

Compounds of the general formula (I): and pharmaceutically acceptable salts thereof, in which A, B, C and D each represent -CH= or -N=, with the proviso that at least one of them is -N=; X represents -NH-, -O- or -S-; Y represents -(CH2)p- wherein p is an integer from 0 to 4, -C(CH3)2-, -CH2CH=CH-, -CH2CO-, -CF2- or -CH2COCH2-; R represents a hydrogen atom, a C1-4 alkyl group, a halogen atom or a C1-4 alkoxy group; R represents a hydrogen atom, a hydroxyl group, a saturated or unsaturated C1-6 alkyl group, a C1-6 alkoxy group, a carboxyl group, a saturated or unsaturated C1-12 alkoxycarbonyl group which may be optionally substituted, a cycloalkoxycarbonyl group, a saturated or unsaturated five- or six-membered heterocyclic group containing at least one nitrogen atom optionally with one or more nitrogen and/or oxygen atoms, which may be optionally condensed and/or substituted, -CONR R , -NR R , -OCOR or -NHCONHR wherein R and R , which may be the same or different, represent a C1-6 alkyl group which may be optionally substituted or a cycloalkyl group, and m and n each represent an integer from 0 to 2.