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L-ascorbic acid 2-phosphate magnesium (APMg) salt is a vitamin C derivative frequently used as a raw material in cell and tissue therapy. APMg is not only used as a replacement of the unstable ascorbate, but also shows additional cell-biological functionalities. However, its unknown structural characteristics hamper the mechanistic elucidation of its biological role. Therefore, different techniques were applied for APMg structure characterization. Firstly, the stoichiometric composition was characterized by its solvent, ligand and magnesium content. No crystals of APMg could be obtained; however, a single crystal of APNa, the sodium salt of l-ascorbic acid 2-phosphate, was successfully obtained and its crystal structure was elucidated. FT-IR was applied to further clarify the structure of solid APMg. Finally, the structure of APMg in aqueous solution was explored by potentiometric titration as well as FT-IR.

Four Cu(I) cyanide coordination polymers, namely [Cu(L1)(CN)] n (1), [Cu2(L2)(CN)2] n (2), [Cu2(L3)(CN)2] n (3) and [Cu2(L4)(CN)2] n (4) (L1 = 4,4′-bis(1,2,4-triazolyl-1-yl)-biphenyl, L2 = 1,4-bis(5,6-dimethylbenzimidazole)butane, L3 = 1,3-bis(2-methylbenzimidazole)propane, L4 = 1,5-bis(5,6-dimethylbenzimidazole)pentane), were synthesized and structurally characterized by X-ray single-crystal diffraction. The cyanide anions in these complexes were generated in situ by cleavage of the C–C bond of acetonitrile under hydrothermal conditions. Complex 1 possesses a 1D infinite ladder-like chain structure, while complexes 2, 3 and 4 exhibit similar 2D (6,3) networks. Both 3 and 4 are further extended into 3D supramolecular frameworks by C–H···π stacking interactions. The fluorescence properties of the complexes and their catalytic activities for the degradation of Congo red azo dye in a Fenton-like process were investigated.

Two Ni(II) coordination polymers, namely [Ni3(btb)4(nbta)2(H2O)4] n (1) and [Ni(btb)(Hbtc)(H2O)2] n (2) (H3nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, H3btc = 1,2,4-benzenetricarboxylic acid), employing mixed-ligand systems, both containing the rigid N-donor ligand btb (4,4′-bis(1,2,4-triazolyl-1-yl)-biphenyl), have been synthesized and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 shows a two-dimensional network with a binodal (3,4)-connected 3,4L90 topology, while complex 2 features a 1D zigzag chain structure. Both complexes are further extended into 3D supramolecular architectures via strong O–H···O hydrogen bonds. The thermal stabilities and luminescence properties of both complexes have been studied.

Two cobalt(II) coordination polymers, namely [Co(bbdmbm)(tbi)·H2O]n (1) and [Co(bmb)1.5(tbi)]n (2), (bbdmbm = 1,1′-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole), bmb = 1,4-bis(2-methylbenzimidazol-1-ylmethyl) benzene, H2tbi = 5-tert-butyl isophthalic acid), have been synthesized and characterized by physico-chemical and spectroscopic methods and also by single-crystal X-ray diffraction. Complex 1 features a 1D ladder-like chain and is further extended into a 3D supramolecular architecture via strong O–H···O hydrogen bonds. Complex 2 exhibits a 2D corrugated (4,4) network constructed with bmb and tbi ligands, which is further assembled into a 3D 3,4,4-connected supramolecular framework with 3,4,4T25 topology through weak C–H···O hydrogen-bonding interactions. The fluorescence properties and catalytic activities of both complexes for the degradation of Congo red in a Fenton-like process have been investigated.

Two cadmium(II) coordination polymers, [Cd(L)(nda)(H2O)·0.75H2O] n (1) and [Cd(L)(tbta)(H2O)] n (2) (L = 1,3-bis-(2-methylbenzimidazol-1-ylmethyl)benzene, H2nda = 2,6-naphthalenedicarboxylic acid, H2tbta = tetrabromoterephthalic acid), were synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction and powder X-ray diffraction analysis. Both complexes exhibit 2D (6,3) honeycomb-like structures. Complex 1 is further extended into a twofold interpenetrating 3D 4,4-connected mog supramolecular architecture with point symbol of {4.64.8}2{42.62.82} via classical O–H···O hydrogen bonding interactions, while 2 displays a 3D supramolecular framework through π–π stacking interactions. The fluorescence properties and thermal stability of the two complexes were investigated.

Four coordination polymers associated with bent bis(imidazole) 1,3-bis(imidazol-l-yl-methyl)benzene (mbix) and isophthalic acid (H2ip) or 5-methylisophthalic acid (H2mip) ligands, formulated as {[Cd(mbix)(mip)]·H2O} n (1), {[Co(mbix)(mip)]·0.4H2O} n (2) [Ni(mbix)(mip)H2O] n (3) and [Ni(mbix)(ip)] n (4), were synthesized under hydrothermal conditions and characterized by physico-chemical and spectroscopic methods. Complexes 1 and 2 are isomorphous and exhibit a 1D loop-like chain. Complex 3 features a 2D (4,4) layer, which further extends into an unusual 2D (3,5)-connected 3,5L2 double-layered supramolecular network via classical O–H···O hydrogen bonding interactions. Complex 4 is a 3D network, which shows a rare binodal (3,5)-connected 3,5T1 framework. Moreover, the luminescence and catalytic properties of the complexes for the degradation of methyl orange by sodium persulfate in a Fenton-like process are reported.

Two coordination polymers, [Co(L1)(IPA] n (1) and {[Ag(L2)(HMIPA)]·H2O} n (2) (H2IPA = isophthalic acid, L1 = 1,2-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, H2MIPA = 5-methylisophthalic acid, L2 = 1,6-bis(5,6-dimethylbenzimidazol-1-yl)hexane, have been synthesized and characterized by physicochemical and spectroscopic methods, as well as single-crystal X-ray diffraction. In 1, six-coordinated cobalt centers are bridged by L1 and IPA2− ligands to generate a (4,4) two-dimensional layer. However, complex 2 features a 1D chain structure, which is further extended by O–H···O hydrogen bonding interactions into a 2D supramolecular layer with (63) topology. The fluorescence and thermal gravimetric analysis of both complexes were also explored. Furthermore, the complexes 1 and 2 exhibit remarkable catalytic properties for the degradation of methyl orange dyes in a Fenton-like process.

The synthesis and biological activity of a hitherto unknown class of compounds, the imidazolylthiazolidin-4-ones, are described. A two-step procedure has been elaborated starting from our previously described 2-aminoimidazoles. The application of microwave irradiation has been proven to be beneficial for the condensation of the imine with mercaptoacetic acid leading to the formation of imidazolylthiazolidin-4-ones. None of the compounds showed antiviral activity at subtoxic concentrations. Several compounds displayed a moderate cytostatic activity. These data form the basis for further improvement of the potential antiproliferative activity of this class of compounds.