Synthesis, structures and urease inhibitory activities of three silver(I) complexes derived from 2,6-dichlorophenylacetic acid

Three new silver complexes based on 2,6-dichlorophenylacetate (dcpa), namely [Ag-2(dcpa)(2)](n) (1), [Ag(NH3)(2)] (dcpa) (2), and [Ag-3(N,N-eten)(dcpa)(3)](2) (3) (N,N-eten = N,N-diethylethylenediamine), were synthesized and structurally characterized. The dcpa ligand adopts a mu(2)-eta(1):eta(1) bridging coordination mode in silver complexes 1 and 3, whereas it is a non-coordinating counter anion in silver complex 2. Complex 1 shows a two-dimensional sheet polymer in which the dimeric [Ag(dcpa)](2) units with a short Ag-Ag separation of 2.783 angstrom are linked to each other by weak Ag-O and Ag-Cl interactions. Complex 2 contains a linear [Ag(NH3)(2)](+) cation and a dcpa anion, which constructs a two-dimensional sheet structure via intermolecular N-H center dot center dot center dot O interactions. Complex 3 features an unusual discrete hexanuclear silver(I) dimer, [Ag-3(N,N-eten)(dcpa)(3)](2), formed by Ag-O and argentophilic interactions (Ag3 center dot center dot center dot Ag3(#) = 3.335 angstrom), which are further connected by intermolecular N-H center dot center dot center dot O interactions to offer a one-dimensional ladder-like chain. The urease inhibitory activities of the obtained silver complexes 1, 2 and 3 were investigated and complex 3 was proven to be a potent inhibitor against jack bean urease.