The invention relates to compounds corresponding to formula (I): ##STR00001## in which: Ar represents a mono- or disubstituted phenyl; R.sub.1 represents an unsubstituted or substituted phenyl; R.sub.2 represents: a pyridyl; an unsubstituted or substituted phenyl; a benzyl that is unsubstituted or substituted on the phenyl; R.sub.2 may moreover represent: a heterocyclic radical; R.sub.3 represents various values. The invention also comprises methods for the compounds preparation, formulations comprising them and therapeutic applications thereof.