Compounds of formula (I): wherein: m and n represent 1 or 2, A represents a pyrrolyl group, X represents a C(O), S(O) or SO2 group, R1 and R2 represent an alkyl group or, together with the nitrogen atom carrying them, form a heterocyclic group, R3 and R4, together with the atoms carrying them, form a heterocyclic group, R5 represents a hydrogen atom or an alkyl group, R6 represents a hydrogen atom or a halogen atom. Medicinal products containing the same which are useful in treating cancer.