N-substituted heterocyclic derivatives, their preparation and the pharmaceutical compositions in which they are present

A compound of the formula ##STR43## in which:

• R.sub.1 and R.sub.2 are similar or different and are each independently hydrogen or a group selected from a C.sub.1 -C.sub.6 alkyl, a C.sub.1 -C.sub.4 alkoxy, an amino, an aminomethyl, a carboxyl, an alkoxycarbonyl in which the alkoxy is C.sub.1 -C.sub.4, a cyano, a tetrazolyl, a methyltetrazolyl, a methylsulfonylamino, a trifluoromethylsulfonylamino, a trifluoromethylsulfonylaminomethyl, an N-cyanoacetamide, an N-hydroxyacetamide, an N-(4-carboxy-1,3-thiazol-2-yl)acetamide, a ureido, a 2-cyanoguanidinocarbonyl, a 2-cyanoguanidinomethyl, an imidazol-1-ylcarbonyl and a 3-cyano-2-methylisothioureidomethyl, with the proviso that at least one of the substituents R.sub.1 or R.sub.2 is other than hydrogen;
• R.sub.3 is a hydrogen, a C.sub.1 -C.sub.6 alkyl which is unsubstituted or substituted by one or more halogen atoms, a C.sub.2 -C.sub.6 alkenyl, a C.sub.3 -C.sub.7 cycloalkyl, a phenyl, a phenylalkyl in which the alkyl is C.sub.1 -C.sub.3, or a phenylalkenyl in which the alkenyl is C.sub.2 -C.sub.3, said phenyl groups being unsubstituted or monosubstituted or polysubstituted by a halogen atom, a C.sub.1 -C.sub.4 alkyl, a C.sub.1 -C.sub.4 halogenoalkyl, a C.sub.1 -C.sub.4 polyhalogenoalkyl, a hydroxyl or a C.sub.1 -C.sub.4 alkoxy;
• and
• either
• R.sub.4 and R.sub.5 are each independently a C.sub.1 -C.sub.6 alkyl, a phenyl or a phenylalkyl in which the alkyl is C.sub.1 -C.sub.3, said alkyl, phenyl and phenylalkyl groups being unsubstituted or substituted by one or more halogen atoms or by a group selected from a C.sub.1 -C.sub.4 perfluoroalkyl, a hydroxyl and a C.sub.1 -C.sub.4 alkoxy;
• or R.sub.4 and R.sub.5 together form a group of the formula .dbd.CR.sub.7 R.sub.8, in which R.sub.7 is hydrogen, a C.sub.1 -C.sub.4 alkyl or a phenyl and R.sub.8 is a C.sub.1 -C.sub.4 alkyl or a phenyl;
• or else R.sub.4 and R.sub.5 together are either a group of the formula (CH.sub.2).sub.n or a group of the formula (CH.sub.2).sub.p Y-(CH.sub.2).sub.q, in which Y is either an oxygen atom, or a sulfur atom, or a carbon atom substituted by a C.sub.1 -C.sub.4 alkyl group, a phenyl or a phenylalkyl in which the alkyl is C.sub.1 -C.sub.3, or a group N--R.sub.6, in which R.sub.6 is a hydrogen, a C.sub.1 -C.sub.4 alkyl, a phenylalkyl in which the alkyl is C.sub.1 -C.sub.3, a C.sub.1 -C.sub.4 alkylcarbonyl, a C.sub.1 -C.sub.4 halogenoalkylcarbonyl, a C.sub.1 -C.sub.4 polyhalogenoalkylcarbonyl, a benzoyl, an alpha-aminoacyl or an N-protecting group, or R.sub.4 and R.sub.5, together with the carbon atom to which they are bonded, form an indane or an adamantane;
• p+q=m;
• n is an integer between 2 and 11;
• and
• m is an integer between 2 and 5;
• or
• R.sub.4 is a C.sub.1 -C.sub.6 alkyl which is unsubstituted or substituted by one or more halogen atoms;
• and
• R.sub.5 is a cycloalkyl or a cycloalkylmethyl, the cycloalkyl being C.sub.3 -C.sub.7, which is unsubstituted or substituted by one or more halogen atoms;
• or R.sub.4 and R.sub.5 are each a cyclopropyl;
• X is an oxygen atom or sulfur atom;
• and
• z and t are zero or one is zero and the other is one;
• and its salts.