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A major threat to public health worldwide is that the antimicrobial activity of the established drugs is constantly reduced due to the resistance that bacteria develop throughout the years. Some transition metal complexes show higher antibacterial activity against several bacteria compared to those of clinically used antibiotics. Novel classes of molecules provide new challenges and seem promising to solve the crisis that the overuse of antibiotics has led over the last years. This review discusses the challenges of chromium-based metallodrugs as antimicrobial agents. In particular, the synthetic routes, the structural characteristics, as well as the antimicrobial activity of 32 chromium (III) complexes have been presented.

Since the discovery of the anticancer properties of cis-platin the road for the development of less toxic and more specific metal ion based anticancer drugs has opened. Based on the low toxicity of VsupIV/V/sup, MosupVI/supand ZnsupII/supmetal ions, their binuclear hydroquinonate complexes have been synthesized and their biological activity towards their anticancer properties on various cancerous and non-cancerous cell lines has been evaluated. The new complexes of ZnsupII/supwith the ligands 2,5-bis((bis(pyridin-2-ylmethyl)amino)methyl)benzene-1,4-diol (Hsub2/subbpymah) and 2,2'-(((2,5-dihydroxy-1,4-phenylene)bis(methylene))bis((carboxymethyl)ammoniumdiyl))diacetate (Hsub6/subbicah) have been synthesized and characterized by X-ray crystallography in solid state andsup1/supH NMR in aqueous solution. The binuclear nature of the complexes increases their hydrolytic stability in aqueous solutions at pD 7.0, depending on the metal ion. The most hydrolytic stable VsupV/supand ZnsupII/suphydroquinonate complexes show to activate Osub2/subtowards oxidation of mercaptoethanol in aqueous solutions at physiological pHs. Only the strongest oxidant, the VsupV/supcomplex with bicahsup6-/sup, significantly activates the intracellular radical oxygen species (ROS) generation. Apparently, the mercaptoethanol oxidation experiment vs time can be used as a preliminary experiment for the prediction of the in vitro ROS generation activity of the complexes in aqueous solutions.

Colorectal cancer is a major threat to the society causing the death through metastasis to several patients with stage IV. Computational tools provide a relatively quick procedure in order to evaluate several molecules for their drug activity. Prenylated flavonoids are well known for their anticancer properties even in colon cancer. Here, we provided altered structures of chalcones, based on theoretical studies that are showing better binding affinities to several colon cancer related proteins. Using molecular docking and dynamics, alongside with density function theory and ADMET studies we are representing two new derivatives of Xanthohumol prenylated flavonoids having promising results against this disease.

Using UV–Vis, FT-IR, fluorescence spectroscopy and protein-ligand docking, the interactions between the zinc complexes with drug analogues and bovine serum albumin were investigated. In addition, considering the ubiquitous presence of zinc ions in the human system, we studied the interactions between this ion with hymecromone, dihydropyridine analogue, and acetamide, as well as the pH influence on these systems. The complexes were synthesized by interaction between the ligands and the Zn (II) ion in a 2:1 M ratio. Elemental analysis, FT-IR, and UV–Vis spectroscopy studies investigated the structure of the synthesized complexes. Fluorescence spectroscopy, UV–Vis, molecular docking and molecular dynamics were used to study the interactions of the Zn complexes with the BSA. The drug-Zn (II) system's pH effect was investigated using UV–Vis spectroscopy. After the complexation with the zinc, the drug molecules exhibited higher apparent binding affinity to BSA. BSA's fluorescence efficiency by the drug analogues was enhanced. In addition, molecular modelling was used to classify the residue of amino acids in the BSA playing key roles in this binding interaction. An increase in pH appears to contribute to alkaline hydrolysis of the Zn (II) molecules.

Novel vitamin E chelate derivatives and their VIV/V complexes have been synthesized and characterized, and their anticancer properties have been evaluated. The new complexes have been designed to exhibit enhanced cytotoxicity by combining high lipophilicity with the properties of vanadium to induce the formation of reactive oxygen species (ROS). In particular, the β-tocopherol derivatives with iminodiethanol (β-tocDEA) and dipicolylamine (β-tocDPA) as well their VV and VIV complexes, [VVO(β-tocDEA] and [VIVO(β-tocDPA] have been synthesized and characterized by Nuclear Magnetic Resonance (NMR), Ultra Violet-Visible (UV–Vis) and Electron Paramagnetic Resonance (EPR) spectroscopies. Although the β-tocopherol compounds exhibit antioxidant activity their complexes induce formation of radicals. In addition, two vanadium amphiphilic complexes of 2,2′-((2-hydroxyoctadecyl)azanediyl)bis(ethan-1-ol) (C18DEA) and 1-(bis(pyridin-2-ylmethyl)amino)octadecan-2-ol (C18DPA) known to activate O2 and produce ROS were synthesized and characterized (C. Drouza, A. Dieronitou, I. Hadjiadamou, M. Stylianou, J. Agric. Food. Chem., vol. 65, 2017, pp. 4942–4951). The four amphiphilic vanadium complexes exhibit enhanced hydrolytic stability. All compounds found to be cytotoxic for cancer cells exhibiting activity similar or higher to cis-platin.

A novel method for the speciation and quantification of the minor OH-molecules in complex matrices in a one pot experiment based on 19F NMR spectroscopy is demonstrated. The method exerts high resolution and sensitivity comparable with conventional methods and gives reliable results when directly applied to edible oils.