Synthesis of Novel Pb, Mn, Zn, Ag, Co and Cu Complexes With Coumarine Derivative Moiety and Their Antibacterial Activities

Abstract

Coumarine derivatives often show significant antibacterial activities. A number of coumarine metal complexes have a wide range of biological activity. In order to find new biological active coumarine derivatives, we prepared new coumarin complexes of Pb, Mn, Zn, Ag, Co and Cu (2–7) with 3‐nitro‐4‐(heteroaryl‐2‐ ylamino)‐coumarine derivatives 1, in very good yields. Synthesized coumarin metal complexes (2–7) were investigated for antibacterial activities using agar diffusion method (in vitro) against Staphylococcus aureus and Escherichia coli. Applying the disc method, we measured diameters of the inhibition zone around disc which are previously wetted with N,N‐DMF solution of compounds (2 – 7) in concentration 1 mg/mL, 3 mg/mL and 5 mg/mL. These new synthesized compounds showed moderate activity in reducing the microbial growth (6.5–13 mm). Comparing the inhibitory activities of the tested complexes, it was found that these complexes were a bit more active than coumarine compound 1.