Synthesis, crystal structure and biological properties of a bismuth(III) Schiff-base complex

In this paper, a new bismuth(III) Schiff-base complex [Bi9O8(vanen)3(NO3)2(CH3OH)2(H2O)]·3NO3·5.5H2O was synthesized by reaction of [H2vanen = N,N′-ethylene bis(3-methoxysalicylideneimine)] and Bi(NO3)3·5H2O in methanol at 45–60 °C. The inhibitory effects of the complex and its ligand on Schizosaccharomyces pombe (S. pombe) growth were investigated by microcalorimetry. The experimental results indicated the complex had a stronger inhibitory activity towards S. pombe than that of the ligand. The interaction between bovine serum albumin (BSA) and the complex under physiological conditions was studied by fluorescence spectroscopy. The complex had a quite strong ability to quench the fluorescence of BSA and their combination reactions were a static quenching process. The complex could bind BSA via a binding site and the binding distance r was 3.52 nm. The synchronous fluorescence spectroscopy further revealed that the complex had partly inserted into the hydrophobic pocket of BSA.