A broad study of two new promising antimycobacterial drugs: Ag(I) and Au(I) complexes with 2-(2-thienyl)benzothiazole

Synthesis, characterization, DFT simulation and biological assays of two new metal complexes of 2-(2-thienyl)benzothiazole – BTT are reported. The complexes [Ag(BTT)2NO3] – AgBTT2 and [Au(BTT)Cl]·½H2O – AuBTT were obtained by mixing the ligand with silver (I) nitrate or gold(I) chloride in methanolic solution. Characterization of the complexes were based on elemental (C, H, N and S), thermal (TG-DTA) analysis, 13C and 1H NMR, FT-IR and UV–Vis spectroscopic measurements, as well as the X-ray structure determination for AgBTT2. Spectroscopic data predicted by DFT calculations were in agreement with the experimental data for both complexes. The ligand BTT was synthesized by the condensation of 2-thiophenecarboxaldehyde and 2-aminothiophenol in a microwave furnace. AgBTT2 has a monomeric structure. Both complexes show a good activity against Mycobacterium tuberculosis. Free BTT shows low antitubercular activity.

The complexes [Ag(BTT)2NO3] – AgBTT2 and [Au(BTT)Cl]·½H2O – AuBTT were characterized by elemental (C, H, N and S), thermal (TG-DTA) analyses, 13C and 1H NMR, FT-IR and UV–Vis spectroscopic measurements, as the X-ray structure determination for AgBTT2. Spectroscopic data predicted by DFT calculations are in agreement with experimental data for both complexes. Both complexes show good activity against Mycobacterium tuberculosis.Figure optionsDownload as PowerPoint slideHighlights
► Two new silver(I) and gold(I) complexes with 2-(2-thienyl)benzothiazole.
► X rays studies show a monomeric structure for the Ag(I) complex.
► IR, NMR 13C and 1H permitted to confirm nitrogen coordination only.
► The spectroscopic studies of the compounds were performed by DFT.
► Complexes show biological activities against Mycobacterium tuberculosis.