Cyclic amino compounds

A cyclic amino compound represented by the following formula:

• wherein:
• R1 represents a phenyl group which may optionally be substituted by at least one substituent selected from the group consisting of halogen atoms, C1-C4 alkyl groups, fluoro-substituted-(C1-C4 alkyl) groups, C1-C4 alkoxy groups, fluoro-substituted- (C1-C4 alkoxy) groups, cyano groups and nitro groups;
• R2 represents a substituent selected from the group consisting of
• C1-C8 aliphatic acyl groups which may optionally be substituted by at least one substituent selected from the group consisting of halogen atoms, C1-C4 alkoxy groups and cyano groups,
• benzoyl groups which may optionally be substituted by at least one substituent selected from the group consisting of halogen atoms, C1-C4 groups and C1-C4 alkoxy groups, and
• (C1-C4 alkoxy) carbonyl groups;
• and
• R3 represents a saturated cyclic amino group having five carbon atoms and one ring nitrogen atom, said saturated cyclic amino group being substituted by a group having the formula —S—X— R4 wherein R4 and X are as defined below, said saturated cyclic amino group being attached via the ring nitrogen atom thereof to the carbon atom to which substitutents R1 and R2 are attached,
• R4 represents a substituent selected from the group consisting of
• phenyl groups which may optionally be substituted by at least one substituent selected from the group consisting of halogen atoms, C1-C4 alkyl groups, C1-C4 alkoxy groups, nitro groups and cyano groups,
• C1-C4 alkyl groups which may optionally be substituted by at least one substituent selected from the group consisting of amino groups, hydroxyl groups, carboxyl groups, (C1-C4 alkoxy) carbonyl groups, substituents having the formula —NH—A1, wherein A1 represents an α-amino acid residue, and substituents having the formula —CO—A2, wherein A2 represents an α-amino acid residue, and
• C3-C8 cycloalkyl groups;
• and
• X represents a sulfur atom, a sulfinyl group or a sulfonyl group;
• said cyclic amino group may optionally be further substituted by a group having the formula =CR5R6, wherein R5 and R6 are the same or different and each is independently selected from the group consisting of hydrogen atoms, C1-C4 alkyl groups, carboxyl groups, (C1-C4 alkoxy) carbonyl groups, carbamoyl groups, (C1-C4 alkyl) carbamoyl groups and di- (C1-C4 alkyl) carbamoyl groups;
• or a pharmacologically acceptable salt thereof.