Cefradine Schiff Bases and their Metal Salts as Potential Anti-Infective Agents

A series of schiff bases(3-8) were synthesized by the reaction of cefradine with six different aldehydes/ketones. These Schiff bases (3-8) were treated with different bases/salts (NaOH, KOH, Ca(OH)2, Ba(OH)2, Ag(NO)3) to get their metal salts. The structures of the products were as-certained by spectroscopic data. The synthesized compounds were tested for biological activities against Staphylococcus aureus (gram-positive bacterium) and Escherichia coli (gram-negative bacterium). In general, low activities in most of the synthesized compounds were observed. A general reduction in the activities of most of the synthesized compounds in com-parison to cefradine can be linked to the unavailability of the free amino group of cefradine by its involvement in the synthesis of imine derivatives. All the synthesized compounds were evaluated for anti-bacterial activity against two bacterial strains S.aureus and E.coli. Compound 23 shows the best activity against both the strains S. aureus and E.coli. Compounds 18, 5, 11 and 27 show good activity against S. aureus while compounds 5, 26, 27, 3, 13, 18, 19 show good activity against E. coli. Reduced activities of most of the synthesized derivatives in comparison to cefradine can be linked to unavailability of free NH2 group of cefradine for any interaction by its involvement in derivatization.