Two two‐dimensional supramolecular copper(II) and cobalt(III) complexes derived from a new quinazoline‐type ligand: Syntheses, structures, and spectral, thermal, electrochemical and antimicrobial activity studies

A highly efficient yet stable salamo-type fluorescent chemosensor with multiple responses to Cu2+ and S2−

A new salamo-type compound H3L has been synthesized, and exploited as a chemosensor with multiple responses to Cu2+ and S2−. The crystal structure of the Cu(ii)  complex has been determined by X-ray crystallographic analysis.

A highly sensitive and selective bis(salamo)-type fluorescent chemosensor for identification of Cu2+ and the continuous recognition of S2-, Arginine and Lysine

A novel bis(salamo)-type chemosensor H₃L was synthesized and characterized. It was found that the sensor molecule can selectively recognize Cu²⁺, and its L-Cu²⁺ is highly sensitive to the detection of S^2- anion, Arginine and Lysine when dissolved in ethanol solvent. The sensor H₃L can be used to identify a relay sensor for Cu²⁺, while the L-Cu²⁺ recognizes S^2- anion, Arginine and Lysine with high selectivity and sensitivity over an acceptable physiological pH range. The detection line of the sensor molecule H₃L is 1.02 × 10^-6 M, and its binding constant to Cu²⁺ is 1.54 × 10⁶ M^-1. The detection line of L-Cu²⁺ as a sensor is calculated as 5.57 × 10^-7 M, and its binding constants with S^2- anion, Arginine and Lysine are 2.80 × 10⁵ M^-1, 5.32 × 10⁶ M^-1 and 5.94 × 10⁶ M^-1, respectively. The crystal structure of the Cu(II) complex [Cu₄(L)₂(CH₃OH)₂]·2NO₃ with the sensor molecule H₃L has been determined by single crystal X-ray crystallography.

Fluorescence Properties and Density Functional Theory Calculation of a Structurally Characterized Heterotetranuclear [ZnII2–SmIII2] 4,4′-Bipy-Salamo-Constructed Complex

A new heterotetranuclear complex, [{Zn(L)Sm(NO3)3}2(4,4′-bipy)]·2CH3OH, was synthesized via an unsymmetrical single salamo-like ligand H2L: 6-methoxy-6′-ethoxy-2,2′-[ethylenedioxybis(azinomethyl)]diphenol, with Zn(OAc)2·2H2O, Sm(NO3)3·6H2O, and 4,4′-bipyridine by the one-pot method. The [ZnII2–SmIII2] complex was validated via elemental analysis, powder X-ray diffraction (PXRD) analysis, infrared spectroscopy, and ultraviolet–visible (UV–Vis) absorption spectroscopy. The X-ray single crystal diffraction analysis of the [ZnII2–SmIII2] complex was carried out via X-ray single-crystal crystallography. The crystal structure and supramolecular features were discussed. In addition, while studying the fluorescence properties of the [ZnII2–SmIII2] complex, the density functional theory (DFT) calculation of its structure was also performed.

A high-efficiency salamo-based copper(ii) complex double-channel fluorescent probe

In this paper, a salamo-based copper(ii) complex probe L-Cu²⁺ was synthesized, which combined with copper(ii) ions to form L-Cu²⁺ for the detection of S²⁻ and had a good fluorescence chemical response. Through spectral analysis, we found that S²⁻ could be identified with high sensitivity and selectivity in the presence of various anions and could be used for the detection of S²⁻ by the naked eye. With the addition of S²⁻, the solution color changed from colorless to bright yellow. UV absorption, fluorescence and other characterization methods were carried out, and the mechanism of action was determined. In addition, we performed a visual inspection of H₂S gas, and the probe L-Cu²⁺ could detect S²⁻ in the gas molecules, revealing its potential application value in biology and medicine.

A highly sensitive and selective salamo-based copper(ii) complex probe, L-Cu²⁺, was synthesized; it could be used for the detection of S²⁻ by UV and fluorescence spectroscopies. And it also could detect S²⁻ in gas molecules.

Antimicrobial activities of self-assembled copper(ii), nickel(ii), and cobalt(iii) complexes combined with crystallographic, spectroscopic, DFT calculations and Hirshfeld surfaces analyses

Three 2-D and 3-D Cu(ii), Ni(ii), and Co(iii) complexes were obtained by reaction of HL1 with different metal salts. The complexes were characterized by single-crystal X-ray crystallography and spectroscopic methods, as well as Hirshfeld surface analysis and DFT studies.