New 2,3-dihydrothiazole derivatives against Helicobacter pylori: Synthesis, biological evaluation and molecular docking studies

Abstract

New, selective and effective molecules are needed to prevent Helicobacter pylori infections that cause gastroduodonal disorders. For this purpose, some new 2-hydrazono-2,3-dihydrothiazole derivatives were synthesized and their structures were confirmed by IR, NMR (H-1, C-13, APT, 2D-NMR) and elemental analysis. The antioxidant activities of the compounds were tested and compound 4f was found to be the most potent compound in three different antioxidant tests (CUPRAC, FRAP and DPPH assays). The inhibitory activities of the compounds against H. pylori and urease enzyme were evaluated. In vitro antibacterial activity tests against H. pylori showed that compounds 4b, 4e, 4h and 4n were the most potent compounds with MIC values of 60.0 mu g/mL. Compounds 4k and 4n exhibited higher anti-urease activity than the reference standard thiourea (IC50 = 15.14 mu M) with IC50 values of 0.95 mu M and 3.43 mu M, respectively. The cytotoxicity of the compounds 4h, 4k and 4n on L929 healthy cells was also investigated. Furthermore, molecular docking and MD simulation studies of the most potent compounds 4h, 4k and 4n with urease enzyme were performed. Thus, unlike current urease inhibitors, new compounds have been obtained that possess anti-urease as well as anti-H. pylori activity and low cytotoxicity.