Abstract: The invention concerns novel cdc25 phosphatase inhibitors, and in particular cdc25-C, which correspond to the general formula (I) wherein: A represents a carbocyclic aryl radical optionally substituted 1 to 3 times by one or more radicals independently selected among a halogen atom and an alkyl, hydroxy, alkoxy, alkylthio or NR1R2 radical wherein R1 and R2 represent a hydrogen atom or an alkyl radical or R1 and R2 form together with the nitrogen atom a heterocycle of 4 to 7 members comprising 1 to 2 heteroatoms, the members required to complete the heterocycle being selected independently among the CR3R4—, —O—, —S and NR5-radicals, R3 and R4 representing independently each time they are involved a hydrogen atom or an alkyl, hydroxy, alkoxy, amino, alkylamino or dialkylamino radical, and R5 representing independently each time it is involved a hydrogen atom or an alkyl radical, or A represents a phenyl radical substituted by a phenyl radical optionally substituted 1 to 3 times by one or more radicals selected