The invention relates to compound corresponding to formula (I) in which: R is either a halogen atom or a phenyl group optionally substituted with one or more halogen atoms, or with one or more groups selected from (d-C6)alkyl and (d- C6)alkoxy groups or a group selected from a pyridinyl, pyrazolyl, imidazolyl, thienyl, furyl and pyrrolyl, it being possible for this group to be optionally substituted with one or more (C1-C8)alkyl groups in the form of a base or of an addition salt with an acid, and also in the form of a hydrate or of a solvate. The invention is also for method for preparation of said compound and composition compR ising it.
