Joanna Masternak

Assembling novel Cd(II) complexes with multidentate nitrogen donor ligands obtained in situ from the system: zerovalent copper, cadmium oxide, 1-hydroxymethyl-3,5-dimethylpyrazole and ammonium thiocyanate.

A novel 3D coordination polymer [Cd2(L(1))(2)(SCN)(4)(MeOH)(2)](n) (1) and monomeric [Cd(NCS)(2)L(2)] (2) (L(1) = urotropine, L(2) = tris(1-(3,5-dimethylpyrazolylmethyl))amine) have been prepared in a one-pot synthesis using 1-hydroxymethyl-3,5-dimethylpyrazole as the starting ligand. The most prominent feature is the formation in situ of the organic compounds: urotropine and scorpionate-tripodal ligands.

Synthesis and physicochemical characterization of two lead(II) complexes with O-, N-donor ligands. Lone pair functionality and crystal structure.

A dinuclear [Pb2(4-CHO-5-MeIm)6(NO3)2](NO3)2 (1) and a polynuclear [Pb(2-pzc)2(H2O)]n (2) complexes (where 5(4)-carbaldehyde-4(5)-methylimidazole (5(4)-CHO-4(5)-MeIm) and pyrazine-2-carboxylic acid (2-pzcH)) have been synthesized and characterized by elemental analysis, IR spectroscopy and X-ray crystallography. Structural determination for complex 1 reveals a cationic species [Pb(4-CHO-5-MeIm)3]2+ connected through bridging nitrate(V) ions. There are also an uncoordinated nitrate ions as counterions. Complex 2 is a three-dimensional architecture consisting of Pb6O12 building units. The pyrazine-2-carboxylato ligand behaves as a chelating agent and a bi-connective bridge. The coordination polyhedra around lead(II) ion could be described as a distorted docecahedron (1) or monocapped trigonal prism (2). The luminescent properties of 1 and 2 investigated in the solid state at room temperature indicate structure-dependent photoluminescent properties. The DFT calculations and the X-ray structural data point on rather hemidirected type of coordination around Pb(II) ions of 1 and 2.

An efficient process to directly convert 1-hydroxymethyl-3,5-dimethylpyrazole to Cd(II) complexes via C–N bond creation: cytotoxicity and factors controlling the structures

We have demonstrated a simple process that involves one-pot, one-step reactions leading to efficient preparation of new cadmium complexes with N4-donating ligands [CdX2L1] (X = I− (1), Br− (2) L1 = tris(1-(3,5-dimethylpyrazolyl)methyl)amine). The most prominent feature of the synthesis is the in situ formation of a new organic tripodal ligand (L1) in a condensation reaction between a starting ligand (1-hydroxymethyl-3,5-dimethylpyrazole) and ammonia. A single-crystal X-ray analysis confirmed that the complexes obtained are monomers (1, 2) with octahedral geometry of the cadmium centres. Complex 3 has a cationic–anionic structure [Cu(LOH)2CH3OH][CdCl4] and has been synthesised by the reaction of CdO and NH4Cl in the presence of zerovalent copper (powder). IR, EPR, 1H and 13C NMR, as well as simultaneous TG/DTG were carried out to characterise the products. Moreover, we try to compare the cytotoxic profile of CdO and cadmium salts with Cd(II) complexes. Besides [CdX2L1] (1, 2) we take into consideration [Cd2(L2)2(SCN)4(MeOH)2]n (4) and [Cd(SCN)2L1] (5) complexes. Biological studies demonstrated that Cd(II) complexes with the N-scorpionate ligand (1, 2 and 5) have similar cytotoxicity, which points to a structure–cytotoxicity relationship. Thus, all the complexes (except 4) exhibited a lower cytotoxic activity compared to a cadmium ion in salts.

Recent Research Trends on Bismuth Compounds in Cancer Chemo- and Radiotherapy

BACKGROUND Application of coordination chemistry in nanotechnology is a rapidly developing research field in medicine. Bismuth complexes have been widely used in biomedicine with satisfactory therapeutic effects, mostly in Helicobacter pylori eradication, but also as potential antimicrobial and anti-leishmanial agents. Additionally, in recent years, application of bismuth-based compounds as potent anticancer drugs has been studied extensively. METHODS Search for data connected with recent trends on bismuth compounds in cancer chemo- and radiotherapy was carried out using web-based literature searching tools such as ScienceDirect, Springer, Royal Society of Chemistry, American Chemical Society and Wiley. Pertinent literature is covered up to 2016. RESULTS In this review, based on 213 papers, we highlighted a number of current problems connected with: (i) characterization of bismuth complexes with selected thiosemicarbazone, hydrazone, and dithiocarbamate classes of ligands as potential chemotherapeutics. Literature results derived from 50 papers show that almost all bismuth compounds inhibit growth and proliferation of breast, colon, ovarian, lung, and other tumours; (ii) pioneering research on application of bismuth-based nanoparticles and nanodots for radiosensitization. Results show great promise for improvement in therapeutic efficacy of ionizing radiation in advanced radiotherapy (described in 36 papers); and (iii) research challenges in using bismuth radionuclides in targeted radioimmunotherapy, connected with choice of adequate radionuclide, targeting vector, proper bifunctional ligand and problems with 213Bi recoil daughters toxicity (derived from 92 papers). CONCLUSION This review presents recent research trends on bismuth compounds in cancer chemo- and radiotherapy, suggesting directions for future research.