Synergistic effect

Sulfones are known to possess various biological activities. Their great potential as bioactive compounds, combined with the easy method of synthesis, make this class a strong candidate for the production of medicines economically. This article deals with the synthesis of a series of ten diaryl sulfones, their antibacterial activity, individually, synergistic antibacterial activity with trimethoprim against E. coli and preliminary QSAR studies. The antibacterial activity was performed by agar diffusion method, against Gram positive and Gram negative bacteria. Few derivatives exhibited antibacterial activity comparable to or better than the standard, sulphamethoxazole, against Gram negative organisms (E. coli and S. dysentrae). Sulfones being folic acid inhibitors, their synergistic effect was checked with trimethoprim on E. coli. Most of the compounds exhibited synergistic effect with trimethoprim, which was better than the combination of trimethoprim and sulfamethoxazole (1:5). Quantitative structure activity relationships studies were performed by multiple linear regression analysis. The antibacterial activity of sulfones was found to correlate well with their dipole moment and ionization potential.