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Abstract: This work presents six CuII, CoII, and NiII supramolecular complexes assembled from a bent dipyridyl ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) and R-isophthalic acids (R =–CH3 for 5-methylisophthalic acid or R =–OCH3 for 5-methoxyisophthalic acid), which have been prepared using the layer-separation diffusion method and fully characterized by IR, elemental analysis, and powder X-ray diffraction (PXRD) techniques. Single-crystal X-ray diffraction indicates that these complexes show 1-D tube-like (for CuII complexes 1 and 2) or discrete cage-like dinuclear (for CoII and NiII complexes 3–6) coordination patterns. Furthermore, extended 3-D supramolecular architectures are constructed via secondary interactions between the coordination arrays, and three types of packing fashions are observed for the dinuclear species 3–6. Structural diversification for these complexes can be properly attributed to the inherent discrepancy of metal ions and the substituent effect of R-isophthalate tectons. [Copyright &y& Elsevier]

A new supramolecular compound [Zn(H2EDTA)(H2O)](Q)2(H2O)2 (1), where H4EDTA=ethylenediaminetetraacetic acid and Q=4-(carboxylate)pyridinium, has been prepared by mild hydrothermal reaction and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. Single-crystal X-ray diffraction of 1 [monoclinic, space group C2/c, a=11.310(4) Å, b=9.704(4) Å, c=23.798(10) Å, β=97.401(10)°, Z=4] revealed that the ZnII ion coordinates to the chelating tetradentate ligand H2EDTA and a water molecule, taking a distorted trigonal-bipyramid geometry. The mononuclear [Zn(H2EDTA)(H2O)] subunits are linked to form two-dimensional layered architectures by the lattice water moieties through O–H⋯O hydrogen bonds, which are further extended to a three-dimensional (3D) supramolecular network by 4-(carboxylate)pyridinium guests (resulting from the ring-opening hydrolysis of 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) through extensive hydrogen-bonding interactions. The 3D supramolecular framework is also stabilized by significant face-to-face π–π stacking interactions between the aromatic pyridinium systems. [Copyright &y& Elsevier]

The reaction of 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (L1) with Cu(OAc)2·H2O salt in a CH3OH/CH3CN medium produces a new monometallic copper(II) complex 1 [Cu(L4)(OAc)(H2O)](H2O)2(CH3CN), where HL4=N-(α-hydroxyl-2-pyridyl)-N′-(α-methoxy-2-pyridyl)ketazine (C13H12N4O2), which was characterized by IR, UV–vis and elemental analysis, and established by X-ray diffraction technique. The results reveal that metal-assisted alcoholysis of L1 leads to the open of the central oxadiazole ring to give a new ligand HL4 during this course. In the crystal structure of complex 1, L4 acts as a tridentate chelating anionic ligand to coordinate to the CuII center, which lies in a square-pyramid coordination environment. Additionally, hydrogen-bonding interactions also play an important role in the self-assembly process. The mechanism of the metal-assisted alcoholysis of L1 in formation of complex 1 was discussed in detail and the spectral properties of 1 were also investigated. [Copyright &y& Elsevier]

• Two novel coordination polymers (CPs) were prepared. • Complex 2 can effectively degrade the methylene blue in the water solution under the irradiation of ultraviolet. • The inhibitory effect of compound against the production of intestinal butyrate was evaluated. Through utilizing a mixed-ligand method, two novel coordination polymers (CPs) containing Co(II) of [Co(L)(dcdps)] n (1) and {Co(L)(bdc)} n (2) [H 2 bdc = 1,4-dicarboxybenzene; H 2 dcdps = 4,4′-sulfonyldibenzoic acid and L = 4,4′-(2,5-bis(methylthio)-1,4-phenylene)dipyridine] have been prepared by the solvothermal method through Co(NO 3) 2 •6H 2 O reacting with the methylthio functionalized dipyridine ligand L in the existence of distinct carboxylic ligands. Compound 2 contains excellent water stability can effectively degrade the methylene blue in the water solution under the irradiation of ultraviolet, which is expected to become a potential photo active material. Furthermore, the inhibitory effect of compound against the production of intestinal butyrate, as well as the HDAC2 expression in colon cancer cells was evaluated. The ELISA test kit was conducted to detect the butyrate content in the intestinal tissue. The real time RT-PCR method was implemented, and the HDAC2 gene relative expression levels in colon cells was measured. Finally, our aim is to generate novel mechanism for the treatment of anti-colon cancer. [ABSTRACT FROM AUTHOR]