Synthesis, a case of isostructural packing, and antimicrobial activity of silver(i)quinoxaline nitrate, silver(i)(2,5-dimethylpyrazine) nitrate and two related silver aminopyridine compounds

Abstract

The synthesis and low temperature crystal structures of [Ag(quinoxaline)]n(NO3)n, 1, [Ag(2,5-dimethylpyrazine)(NO3)]n, 2 and [Ag4(3-aminopyridine)4(NO3)4]n 3 are presented. The quinoxaline compound forms a 1D coordination polymer with the characteristic linear 2-coordination figure of silver(I), the N-Ag-N angle being 164.2(1) degrees, and only weak silver-nitrate interactions. In addition there is an interaction giving pairs of parallel chains as the main structural theme. The 2,5-dimethylpyrazine compound has approximately trigonal-planar coordination, also binding one nitrate at the relatively short Ag-O distances 2.444(3) angstroms and 2.484(3) angstroms, respectively, for the two crystallographically different silver atoms. This also results in a 1D coordination polymer that, despite the large differences in the Ag(I) coordination environment, is isostructural with 1. [Ag4(3-aminopyridine)4(NO3)4]n 3 forms a 2D coordination polymer by bridging nitrate ions. The antimicrobial activity of 1-3, and also of [Ag3(2-aminopyridine)4](NO3)3, 4 was screened for 13 different pathogens and substantial activity was shown for 1 against Escherichia coli and Pseudomonas aeruginosa (MIC 4 microg cm(-3)) and somewhat lower activity was registered against Sarcina lutea and Salmonella typhi for 1, Bordetella bronchiseptica for 2, Salmonella typhi and Pseudomonas aeruginosa for 3, and Escherichia coli and Shigella sonnie for 3 (MIC 8 microg cm(-3)). Only low activity was shown against the yeast Candida albicans for 1, 2 and 4 whereas no activity against this pathogen was registered for 3.

A Silver(I) Coordination Polymer Based on a Schiff Base Ligand: Synthesis, Crystal Structure and Luminescence Properties

“…The average distance Ag(1)-N is 2.33Å, similar to previously reported values [21]. The distance Ag(1)-O is 2.604Å, thus the nitrate is only weakly coordinated to the silver ion [22,23] Table 3. Weak C-H···O hydrogen bond interactions (Å and deg) in the crystal structure of 1.…”

Silver-Based Hybrid Materials from meta- or para-Phosphonobenzoic Acid: Influence of the Topology on Silver Release in Water

“…27,28 Crystalline coordination polymers were also studied for their potent bactericidal action. In this class of material most of the studies involved silver salts coordinated to aza-heterocyclic ligands (pyridyl, 29 pyrazolyl, 30 pyrazinyl 31 ). Recently we reported the first example of an efficient bactericidal silver-based hybrid in which phosphonic and carboxylate functional groups tether the organic part with the silver salt in a 3D arrangement.…”

Synthesis and antimicrobial activities of gold(I) sulfanylcarboxylates

“…Silver compounds have mainly been studied for their widely known antibacterial effect; in fact, silver nitrate and certain silver complexes are still used against local infections [1][2][3]. From this perspective, compounds with Ag kernels have recently been prepared and studied, including examples containing Ag-N [4][5][6][7], Ag-O [8][9][10] and Ag-S [11][12][13][14][15] bonds and some with other additional bonds. In previous papers, we have contributed [14,15] to the study of Ag-S by preparing compounds of the type [Ag (HL)], [Ag 2 …”