Compounds of formula (I):in which: R1 represents a phenyl group or naphthyl group, optionally substituted by one or more atoms or groups chosen, independently of one another, from: halogen, (C1-C6)alkyl, halo(C1-C6)alkyl, (C1-C6)alkoxy, halo(C1-C6)alkoxy, (C1-C6)thioalkyl,-S(O)(C1-C6)alkyl,-S(O)2(C1-C6)alkyl, hydroxyl, hydroxy(C1-C6)alkylene, CHO, COOH, (C1-C6)alkoxy(C1-C6)alkyleneoxy, NRaRb, CONRaRb, SO2NRaRb, NRcCORd, OC(O)NRaRb, OCO(C1-C6)alkyl, NRcC(O)ORe or NRcSO2Re； X represents from 1 to 4 substituents which are identical to or different from one another and which are chosen from hydrogen, halogen, (C1-C6)alkyl or (C1-C6)alkoxy, it being possible for the (C1-C6)alkyl to be optionally substituted by one or more groups chosen from a halogen, (C1-C6)alkoxy or hydroxyl； R2 and R3 represent, independently of one another, a hydrogen atom, a (C1-C6)alkyl group optionally substituted by an Rf group, or a CHO or COOH group； X and R3 can together form, with the carbon atoms which carry them, a carbocycle of 5 to 7 carbon atoms； R4 represents a hydrogen atom or a (C1-C6)alkyl group； Ra and Rb represent, independently of one another, a hydrogen atom or a (C1-C6) alkyl, aryl(C1-C6)alkylene or aryl group； or Ra and Rb together form, with the nitrogen atom which carries them, an azetidine, pyrrolidine, piperidine, azepine, morpholine, thiomorpholine, piperazine or homopiperazine group, this group being optionally substituted by a (C1-C6)alkyl, aryl or aryl(C1-C6)alkylene group； Rc and Rd represent, independently of one another, a hydrogen atom or a (C1-C6)alkyl, aryl (C1-C6)alkylene or aryl group； or Rc and Rd together form a (C2-C5)alkylene group； Re represents a (C1-C6)alkyl, aryl(C1-C6)alkylene or aryl group； or Rc and Re together form a (C2-C5)alkylene group； Rf represents a hydroxyl, oxo, CHO or COOH group, in the form of the base or of an addition salt wit
