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A novel Schiff base [C20H23NO3], has been prepared and characterized using FT-IR, UV-vis, (1)H NMR spectroscopy, elemental analysis and X-ray crystallography. A copper (II) complex [Cu(C20H22NO3)2]·H2O has also been synthesized and characterized. The new ligand and complex thus obtained were investigated by their interaction with calf thymus DNA and BSA using electronic absorption spectroscopy, fluorescence spectroscopy, and thermal denaturation. The intrinsic binding constants Kb of the ligand and Cu (II) complex, with CT-DNA obtained from UV-vis absorption studies were 1.53×10(4)M(-1) and 3.71×10(5)M(-1), respectively. Moreover the addition of the two compounds to CT-DNA (1:2) led to an increase of the melting temperature of DNA up to around 2.61°C for the ligand and 3.99°C for the Cu (II) complex. The ligand and Cu (II) complex bind to CT-DNA via a partial intercalative, as shown by the experimental data. In addition, the albumin interactions of the two compounds were studied by fluorescence quenching spectra, the results indicating that the binding mechanism is a static quenching process. The in vitro cytotoxicity of the two compounds on three different cancer cell lines was evaluated by MTT assay. The results showed that the copper complex exerted enhanced cytotoxicity compared with the Schiff base ligand; thereby, this complex clearly implies a positive synergistic effect. Furthermore, the copper complex showed a high, selective, and dose-dependent cytotoxicity against cancer cell lines.

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Three cadmium coordination polymers, namely, { [CdL-(OAc) and [CdL-(OAc) 2 (H 2 O)] n (3), were synthesized by an exoditopic 1,4-bis(4pyridyl)-2,3-diaza-1,3-butadiene Schiff base ligand (L) and cadmium acetate in the presence of different solvent systems. Single-crystal X-ray diffraction, powder X-ray diffraction, and thermogravimetric analysis showed that 1D ladder pseudopolymorphic compounds (1 and 2) transformed to the solvent-free 1D linear compound 3 through a rare case of water absorption from air at room temperature. Interestingly, compound 3 was transformed to compound 1 through a dissolution− recrystallization structural transformation process. The results illustrated that solvents and humidity have an important role in the formation of pseudopolymorphs with the same or different structural motifs.

Cycloplatinated(ii) complexes 1–4 were synthesized and characterized. All complexes exhibit strong luminescence except 3.

Mononuclear complexes [Pt­(ppy)­(S∧S)] (1a, S∧S = O,O′-di­(cyclohexyl)­dithiophos­phate (ctp); 2a, S∧S = O,O′-di­(butyl)­dithiophos­phate (btp)) and [Pt­(bzq)­(S∧S)] (1b, S∧S = ctp; 2b, S∧S = btp) have been prepared by the reaction of precursor complexes [Pt­(C∧N)­Cl­(dmso)], C∧N = deprotonated form of 2-phenylpyrdine (ppy) and 7,8-benzoquinoline (bzq), and potassium salt of S∧S ligands. All complexes were characterized by NMR spectroscopy, and the structure of 2b was further identified by single crystal X-ray determination. Although the complexes are not luminescent in solution at ambient temperature, they become strong emissive materials (bright green) in solid state (at room temperature) with high quantum yields and long lifetimes in the microsecond domain. In frozen glass state or at low temperature (solid state), these complexes become better emissive in relation to room temperature. UV–vis spectra, supported by TD-DFT calculations, indicate that 1ILCT (intraligand charge transfer) predominates over the other transitions (L = C∧N cyclometalated ligand). Accordingly, 1 and 2 exhibit structured emission bands which display a large involvement of 3LCCT (ligand-centered charge transfer) with lower contribution of 3MLCT (metal to ligand charge transfer) transition in the excited states. Also, biological activities of 1 and 2 were evaluated against three human cancer cell lines including A549 (human lung cancer), SKOV3 (human ovarian cancer), and MCF-7 (human breast cancer). 2a presented an effective potent cytotoxic activity regarding to the cell lines. The cellular localization of 1a and 2a in MCF-7 human cells was investigated by fluorescence microscopy.

The small-ring heterocycle skillfully embraced with pyrrole and pyrazole are well-known for their enriched biological properties. In this article, an efficient green sonochemical approach was designed for the synthesis of...

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