H NMR and thermogravimetric analyses (TGA). The Schiff base ligand behaves as a tetradentate, coordinating through azomethine nitrogen, phenolic oxygen and two carboxylic oxygen atoms. The interaction of these complexes with calf thymus DNA (CT-DNA) was also investigated by spectrometric titration and viscometric measurements. The faint hypochromism of the complexes in the absorption spectra, the remarkable reduction of fluorescence intensity of ethidium bromide (EB) bound DNA, together with a small decrease in the viscosity of the DNA suggest that a partial intercalation may be the preferred binding mode between these two complexes and DNA. The antibacterial activity testing revealed that the complexes and their precursor Schiff base show a weak to moderate activity against Bacillus subtilis, Staphylococcus aureus and Escherichia coli.© Versita Warsaw and Springer-Verlag Berlin Heidelberg.

In the title polymer, [Mn(C8H8O5)(H2O)2]n, the MnII atom is in a distorted octa­hedral coordination mode, binding to the bridging O atom of the bicyclo­heptane unit, two O atoms from corresponding carboxyl­ate groups, one carboxyl­ate O atom from a symmetry-related bridging ligand and two water O atoms. This arrangement leads to the formation of polymeric chains propagating parallel to [001]. The crystal structure is stabilized by several O—H⋯O hydrogen-bonding inter­actions involving the coordinated water mol­ecules as donors and the carboxyl­ate O atoms as acceptors.