BACKGROUND A convenient approach to modulation of the inflammation has an influence on the production of inflammatory mediators - icosanoids, generated in arachidonic acid (AA) metabolism. The common therapeutic activity of non-steroidal anti-inflammatory drugs (NSAID), such as aspirin, includes inhibition of two crucial enzymes of AA metabolism - cyclooxygenase- 1 and -2 (COX-1/2), with certain risk for gastrointestinal and renal intolerance. Ever since the enrolment of COX-2, particularly overabundance of its main products prostaglandin E2 (PGE2) and thromboxane A2 (TXA2) in numerous pathological processes was recognized, it became a significant therapeutic target. OBJECTIVE The aim of this study was to examine the effects of synthesized organo-fluorine compounds on PGE2 and TXA2 production in the inflammation process. METHODS Trifluoromethyl compounds were synthesized from N-benzyl trifluoromethyl aldimine, commercially available 2-methyl or 2-phenyl α-bromo esters (β-lactams trans-1 and trans-2 and trifluoromethyl β-amino ester, respectively) and methyl 2-isocyanoacetate (2-imidazoline trans-4). The reactions proceeded with high geometric selectivity, furnishing the desired products in good yields. The influence of newly synthesized compounds on PGE2 and TXA2 production in human leukemic U937 macrophages on both enzyme activity and gene expression levels was observed. RESULTS Among the tested trifluoromethyl compounds, methyl trans-1-benzyl-5-(trifluoromethyl)- 4,5-dihydro-1H-imidazole-4-carboxylate (trans-4) can be distinguished as the most powerful antiinflammatory agent, probably due to its trifluoromethyl-imidazoline moiety. CONCLUSIONS Some further structural modifications in tested compounds and particularly in the synthesis of different trifluoromethyl imidazolines could contribute to the development of new COX-2 inhibitors and potent anti-inflammatory agents.