| abstract |
The compounds of the formula (I) (see formula) where: X represents an oxygen atom or a. sulfur atom or a CH2 group or (see formula) Rl and R2 represent a hydrogen atom, or a group as defined in the description, A represents an alkylene chain as described in the description, B is as defined in the description, R3 and R4 represent a hydrogen atom or a group as defined in the description, D represents an optionally substituted benzene nucleus, an optionally substituted pyrazine nucleus, an optionally substituted pyrimidine nucleus or a pyridazine nucleus optionally substituted. |