Antimicrobial properties of thiophene derivatives

Abstract

Thiophene ring is important for compound antimicrobial activity. Tested compound with thiophene ring and amide chain showed equal activity with chloroamphenicol against Staphylococcus aureus [1]. Thiophene derivatives were active against Mycobacterium fortuitum [2]. Several dinitrothiophenes proved to be promising antimicrobial agents against Mycobacterium pathogenic strains such as M. avium and M. kansasei [3]. Some thiophene derivatives are also active against protozoa: 2,5-bis-(4- amidinophenyl)thiophene displayed effect against Leishmania donovani and it was more toxic to the parasites than to a cultured mouse macrophage cell line [4]. Antihelminthic activity is possible as well – agents with a thiophene core group were active against larvae of the tapeworm Echinococcus multilocularis [5]. We focused on new thiophene derivatives, some of them containing nitro group. Antimicrobial (antibacterial and antifungal) activity of these compounds was tested in vitro in these bacterial and fungal cultures: Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Bacillus subtilis, Bacillus cereus and Candida albicans. Serial dilution in agar technique was used. The results of experiments in vitro showed that activity against various microorganisms was different. Two compounds containing nitrothiophene group showed activity against B. cereus and one of them was also active against S. aureus, S. epidermidis, B. subtilis and C. albicans (MIC varies in the range of 50-100 μg/ml and lower). The obtained preliminary results offer a great potential for further exploration of thiophene and nitrothiophene derivatives.