Conjugation of a Silver-Based Coordination Polymer with Curcumin: A New Case of an Inorganic Polymeric Co-crystal

A new structural form of the already reported silver based 1D coordination polymer (CP) [(bpy)Ag (OTf)](8) (bpy = 2,2'-bipyridine; OTf = trifluoromethanesulfonate) has been synthesized and fully characterized through single-crystal and powder XRD, DSC, and FTIR analysis. The reaction of both structural forms of the Ag(I) CP with curcumin (curc) afforded the formation of a new solid form, specifically an inorganic polymeric co-crystal between curc and [(bpy)Ag (OTf)] in a 1: 4 molar ratio, respectively. The co-crystal has been characterized both in solution and in the solid state through H-1 NMR, PXRD, DSC, IR, and UV-vis spectroscopies. In addition, a thorough computational study has been carried out to reveal the possible interaction modes between the co-crystal components. The Ag(I) compounds here presented have been preliminarily tested for antimicrobial activity against Staphylococcus aureus and Escherichia coli strains, all showing promising results.