Lipoxygenase catalyzes the first two steps of the transformation of arachidonic acid into leukotrienes which are implicated in host defense reactions. It is well known that many acids possess potent anti-inflammatory activity. Taking into account that compounds bearing a thienyl, naphthyl, pyrollyl, and 2,4-di-tert-butyl-phenol moieties possess anti-inflammatory activity which is related to their capacity to transfer electrons and to scavenge reactive oxygen species, we synthesized some new aryl-acetic acids and we explored their ability to inhibit soybean lipoxygenase, to present antioxidant and anti-inflammatory activities, and to interact with glutathione. The compounds have shown important antioxidant activity, medium anti-inflammatory activity, and very good inhibition of soybean lipoxygenase. Compound 3-(3,5-di-tert-butyl-2-hydroxy-phenyl)-2-phenyl-acrylic acid (1i) showed significant in vitro LO inhibition (IC(50) 65 microM). The results are discussed in terms of structural and physicochemical characteristics of the compounds. The structures of the synthesized compounds were confirmed by spectral and elemental analysis. Their lipophilicity are experimentally determined by RPTLC method.