Silver(I) and copper(I) complexes with a Schiff base derived from 2-aminofluorene with promising antibacterial activity

Abstract By reaction of 2-aminofluorene with 2-pyridinecarboxaldehyde a new Schiff base ( L ) is obtained. The reaction of this ligand with Ag(I) and Cu(I) salts in different stoichiometry leads to the complexes [Ag(CF 3 SO 3 )(L)PPh 3 ] ( 1 ) or [ML 2 ]A (M = Ag, Cu; A = CF 3 SO 3 , ClO 4 or BF 4 ). Structural characterization by X-ray crystallography has been carried out for complexes [AgL 2 ]ClO 4 ( 4 ) and [Ag(L)(PPh 3 ) 2 ](CF 3 SO 3 ) ( 6 ), which confirms the chelate nature of L and the presence of Ag⋯H interactions between two molecules. The biological studies show that Schiff base L presents antibacterial activity in Gram-positive bacteria and E. coli . The coordination to silver increases this activity, but the formation of the copper complex does not generate significant changes.