A total of 31 of thiourea derivatives was prepared reacting 3-(trifluoromethyl)aniline and commercial aliphatic and aromatic isothiocyanates. The yields varied from 35% to 82%. All compounds were evaluated in vitro for antimicrobial activity. Derivatives 3, 5, 6, 9, 15, 24 and 27 showed the highest inhibition against Gram-positive cocci (standard and hospital strains). The observed MIC values were in the range of 0.25-16 μg/ml. Inhibitory activity of thioureas 5 and 15 against topoisomerase IV isolated from Staphylococcus aureus was studied. Products 5 and 15 effectively inhibited the formation of biofilms of methicillin-resistant and standard strains of Staphylococcus epidermidis. Moreover, all obtained thioureas were evaluated for cytotoxicity and antiviral activity against a large panel of DNA and RNA viruses. Compounds 5, 6, 8-12, 15 resulted cytotoxic against MT-4 cells (CC50 ≤ 10 μM).
