Novel 2,3-dihydro-1H-imidazo {1,2-a} pyrimidin-5-one, their preparation and pharmaceutical use

Products of formula (I): Formula ** ** in which: R1 represents an -L-aryl or -L-heteroaryl radical, such that L represents: either a linear or branched alkyl containing 1 to 6 carbon atoms carbon and optionally substituted by a hydroxyl radical, or a CO group, or an L'-X group wherein L 'represents a linear or branched alkyl containing 1 to 6 carbon atoms and X atom oxygen or sulfur; the aryl and heteroaryl radicals are optionally substituted by one or more identical or different halogen atoms and hydroxyl radicals, CN, nitro, -COOH, -COOalk, -NRxRy, radicals - CONRxRy, -NRxCORy, -NRxCO2Rz, - Cory, alkoxy, phenoxy, alkylthio, alkyl, cycloalkyl and heterocycloalkyl; the latter being alkoxy radicals, phenoxy, alkylthio, alkyl and heterocycloalkyl, optionally substituted themselves one or more identical pair or different radicals selected from halogen atoms and -NR VRW; may heterocycloalkyl and heteroaryl radicals also contain an oxo radical; R2 represents a hydrogen atom or an alkyl radical; R3 represents an alkyl radical optionally substituted with one or more halogen atoms; R4 represents a hydrogen atom or a halogen atom; being NRxRy such that Rx represents a hydrogen atom or an alkyl radical and Ry represents a hydrogen atom, a cycloalkyl radical or an alkyl radical optionally substituted by one or more identical or different hydroxyl, alkoxy, -NR VRW and heterocycloalkyl radicals ; or Rx and Ry form, with the nitrogen atom to which they are attached, a cyclic radical containing from 3 to 10 members and optionally one or more other heteroatoms selected from O, S, NH and N-alkyl, wherein this cyclic radical optionally substituted; being -NR VRW such that Rv represents a hydrogen atom or an alkyl radical and Rw represents a hydrogen atom, a cycloalkyl radical or an alkyl radical optionally substituted by one or more identical or different hydroxyl, alkoxy, heterocycloalkyl radical; or Rv and Rw form, with the nitrogen atom to which they are attached, a cyclic radical containing from 3 to 10 members and optionally one or more other heteroatoms selected from O, S, NH and N-alkyl, wherein this cyclic radical optionally substituted; the cyclic radicals may form Rx and Ry or Rv and Rw respectively with the nitrogen atom to which they are attached being optionally substituted with one or more identical or different halogen atoms radicals, alkyl radicals, hydroxyl, oxo, alkoxy, NH2; NHalk and N (alk) 2; Rz Ry represents values ​​except hydrogen; It is Rx, Ry and Rz in -NRxCORy, -CORy and selected from the meanings indicated above for Rx, Ry NRxCO2Rz, and Rz radicals; being the alkyl (alk), alkoxy and alkylthio previous linear or branched and containing 1 to 6 carbon atoms, said products of formula (I) in any of the possible isomeric forms, racemic, enantiomeric and diastereoisomeric, and the salts of addition with mineral and organic acids or with mineral and organic bases of said products of formula (I).