The invention relates to compounds corresponding to formula (I), in the form of the base or of an acid-addition salt: in which n is equal to 0, 1, 2, 3 or 4; m is equal to 0, 1 or 2; o is equal to 0 or 1; X represents a group —CH2, —CH(R′)—, —NH(R′)— or a heteroatom chosen from O and S, it being understood that R′ represents a group —(C1-C5)alkyl, —(C1-C5)alkoxy, —CH2-aryl, —C(O)R5 or —COOR5; R1, R2, R5 are as defined in the specification.