Oxoimidazolinealkanoic acids and their salts and esters, their preparation and pharmaceutical compositions containing them

omega -(2-Oxo-4-imidazolin-1-yl) alkanoic acids and salts and esters thereof of the formula: I in which n denotes an integer from 1 to 8, R1 denotes H, a non-toxic cation or a straight-chain or branched, saturated hydrocarbon group of 1 to 6 carbon atoms, and R2 denotes an unsubstituted or substituted aromatic radical of formula or naphthyl, the substituents X and Y being identical or different and each representing H, halogen or alkoxy have strong antithrombotic activity and an analgesic effect.