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In order to investigate the structural features and antiproliferative activity of Pd(II) complexes containing halogenated ligands with different flexibility, several Schiff base and reduced Schiff base Pd(II) complexes, namely X1X2PicPd, X1X2PyPd, X1X2Pic(R)Pd, and X1X2Py(R)Pd (where X 1 = X 2 = Cl, Br and I; Pic: 2-picolylamine; Py = 2-(2-pyridyl)ethylamine), were synthesized and characterized by spectroscopic methods and, in the case of Br2PyPd, Cl2Py(R)Pd and ClBrPy(R)Pd, also by X-ray crystallography. The results of the X-ray crystallography showed that in both series of complexes the Pd(II) ion has a distorted square-planar geometry, although the coordination modes of the two ligands are different. In the Schiff base-type complexes the ligand acts as a tridentate chelate with NN'O donor atoms, whereas in the reduced Schiff base-type complexes the ligand acts as a bidentate chelate with NN' donor atoms. In both series of complexes, the chloride ions occupy the residual coordination sites of the Pd(II) ion. TD-DFT calculations were performed for a better understanding of the UV-Vis spectra. From these calculations it was found that the signal appearing at ∼400 nm in the complexes with reduced Schiff base ligands (X1X2Pic(R)Pd and X1X2Py(R)Pd) is mainly due to a HOMO → LUMO transition, while for the Schiff base complex ClBrPyPd the signal is due to a HOMO → LUMO+1 transition. For the complex I2PicPd, combinations of HOMO-4 → LUMO and HOMO-2 → LUMO transitions were found to be responsible for that signal. In regard to the biological activity profile, all complexes were first investigated as proteasome inhibitors by fluorometric methods. From these enzymatic assays, it emerged that they are good inhibitors with IC 50 values in the low-micromolar range and that their inhibitory activity is strictly related to the presence of the metal ion. Subsequently they were also subjected to cell-based assays (the resazurin method) to assess their antiproliferative properties by using two leukemic cell lines, namely the drug-sensitive CCRF-CEM cell line and its multidrug-resistant sub-cell line CEM/ADR5000. In this test they displayed IC 50 values in the sub-micromolar and low-micromolar range determined for a selected metal complex (Br2Pic(R)Pd) and ligand (Cl2Pic(R)), respectively. Moreover, docking studies were performed on the two expected molecular targets, i.e. proteasome and DNA, to shed light on the mechanisms of action of these types of Pd(II) complexes.

A new Azo-Schiff base ligand (H 2 L) was designed and synthesized as a cation chemosensor. The chemosensor H 2 L as dual chemosensor showed selective fluorescence recognition of Al 3+ with a noticeable fluorescence enhancement and colorimetric detection of Co2 + in aqueous ethanol solution. The H 2 L exhibits a linear response toward Al 3+ ions in the concentration range of 1.91 × 10 -8  M to 4.8 × 10 -6  M with a limit of detection of 1.91 × 10 -8  M. The sensing mechanism of sensor H 2 L toward Al 3+ was investigated by 1H NMR and IR spectroscopies. Fluorescence switch based on the control of EDTA and Al 3+ proved H 2 L could act as a reversible chemosensor. The molecular structure of [NiL] complex has been determined by X-ray crystallography., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Coordinative polymers (CP) are a subclass of Metal-organic frameworks (MOFs) with porous microstructures which have been widely synthesized in recent years and applied in various fields especially in catalysis science. In this work Coordinative polymers (CP) of nickel and citric acid (CA) was prepared as a new catalyst (Ni-CP) and applied in organic multicomponent reactions. The obtained catalyst was characterized by SEM, WDX, EDS, AAS, FT-IR, XRD and BET analysis. N 2 adsorption-desorption isotherms indicate good BET surface area for Ni-CP; therefore can be employed as an efficient catalyst in multicomponent reactions for the synthesis of polyhydroquinoline and 2,3-dihydroquinazolin-4(1H)-one derivatives. Finally, this catalyst was recovered and reused several consecutive times., (© 2021. The Author(s).)

A new dialdehyde was designed and synthesized containing naphthalene groups, and then its macrocycle was prepared with 1,4-diaminobuthan. A modified nanoprecipitation method has been reported for the preparation of the nanoparticles. In this method, to obtain nanoparticles with small particle sizes, the nucleation rate was increased with decreasing of the mixing time. The organic nanoparticles were used for turn-off fluorescence response of low concentration of Sn 2+ ions over cations such as Cs + , K + , Na + , Ba 2+ , Ca 2+ , Mg 2+ , Al 3+ , Pb 2+, Zn 2+ , Cu 2+ , Ni 2+ , Co 2+ , Fe 2+ , Mn 2+ , Ag + , Cd 2+ , and Hg 2+ and ions in aqueous buffer solution. The limit of detection was 5.4 nM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, the aim was to determine whether adding vitamin D to the standard therapeutic regimen of schizophrenic male patients with inadequate vitamin D status could improve some aspects of the symptom burden or not. This study was an open parallel label randomized clinical trial. Eighty patients with chronic stable schizophrenia with residual symptoms and Vitamin D deficiency were recruited randomly and then received either 600000 IU Vitamin D injection once along with their antipsychotic regimen or with their antipsychotic regimen only. Serum vitamin D was measured twice: first at the baseline and again on the fourth month. Positive and Negative Syndrome Scale (PANSS) was assessed at the baseline and on the fourth month. During the study, the vitamin D serum changes in vitamin group and control group were 22.1 ± 19.9(95%CI = 15.9-28.8) and 0.2 ± 1.7(95%CI = 0.2-0.8) (ng/mL) (p<0.001) respectively. The changes of PANSS positive subscale score (P) were -0.1±0.7 (95%CI =-0.3-0.1) and 0.00 ± 0.8 (95%CI = -0.2-0.2) in vitamin D and control group respectively (p=0.5). The changes of PANSS negative subscale score (N) were -0.1 ± 0.7 (95%CI = -0.3-0.05) and -0.1 ± 0.5 (95%CI = -0.2-0.04) in vitamin D and control group respectively (p = 0.7) and there was a negative but not significant correlation between serum vitamin D level changes and PANSS negative subscale score (r = -0.04, p = 0.7). We did not find a relationship between serum vitamin D level changes and the improvement of negative and positive symptoms in schizophrenic patients and more randomized clinical trials are required to confirm our findings.

A new naphthalene derivative receptor (L) was synthesized and characterized with common spectroscopic methods. L exhibited a strong fluorescence enhancement in the presence of trace amounts of Pb(2+), attributable to photoinduced electron transfer (PET) effect, which also displayed high selectivity over a series of other metal cations (Na(+), K(+), Cs(+), Mg(2+), Ba(2+), Cr(3+), Mn(2+), Fe(3+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+) and Ag(+)) in acetonitrile/H2O (9:1, v/v) mixture., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A new macrocyclic nano-chemosensor (L) was synthesized and characterized by common spectroscopic methods. Spectral properties of fluorescent macrocycle L were studied either as solution in ethanol or as insoluble nanoparticles in aqueous buffer solution. The nano-chemosensors with size about 40nm were prepared by nanoprecipitation method. The influence of metal cations such as Na(+), K(+), Cs(+), Mg(2+), Ba(2+), Al(3+), Pb(2+), Cr(3+), Mn(2+), Fe(3+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+) and Ag(+) on the spectroscopic properties of the chemosensor in aqueous buffer solution were investigated by means of emission spectrophotometry. The macrocycle was found to be as an effective fluorescence sensor for Cs(+) ions., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A new naphthalene derivative receptor (H2L) was synthesized. The chemosensor (H2L) exhibited a strong fluorescence enhancement in the presence of trace amounts of Al(3+), attributable to chelation-enhanced fluorescence (CHEF) effect, which also displayed high selectivity over a series of other metal cations (Na(+), K(+), Cs(+), Mg(2+), Ba(2+), Pb(2+), Cr(3+), Mn(2+), Fe(3+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+) and Ag(+)) in ethanol., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A novel macrocyclic chemosensor (L) has been synthesized and characterized by common spectroscopic methods. Spectral properties of fluorescent macrocycle L were studied either as solution in ethanol or as insoluble nanoparticles in aqueous buffer solution. The nano-chemosensors with size about 35nm were prepared by nanoprecipitation method. The influence of metal cations such as Na(+), K(+), Cs(+), Mg(2+), Ba(2+), Al(3+), Pb(2+), Cr(3+), Mn(2+), Fe(3+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+) and Ag(+) on the spectroscopic properties of nano-chemosensor (L) in aqueous buffer solution were investigated by means of emission spectrophotometry. The macrocycle was found to be as an effective fluorescence sensor for Al(3+) ions., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The crystal structure of the title compound, (C(6)H(16)N)(2)[CoCl(4)], is comprised of a tetrahedral [CoCl(4)](2-) anion and two independent triethyl-ammonium cations. The latter are featureless while the [CoCl(4)](2-) anion exhibits typical Co-Cl bond lengths [2.2428 (15)-2.2847 (16) Å] and a Cl-Co-Cl angular range of 107.58 (6)-112.73 (7)°. In the crystal, N-H⋯Cl hydrogen bonds between the two crystallographically independent cations and the [CoCl(4)](2-) anion generate discrete ion triplets. The two Co-Cl bonds involved in these inter-actions are slightly longer than the remaining two.

1-((E)-(2-((2-nitrobenzyl)(2-((E)-(2-hydroxynaphthalen-1-yl)methyleneamino)ethyl)amino)ethylimino)methyl)naphthalen-2-ol (H(2)L), The new compound featuring two naphthalene units was synthesized and characterized. We find that H(2)L has high selectivity and sensitivity to detect Zn(2+) ion over other metal ions such as Na(+), Ag(+), Cd(2+), Co(2+), Cr(3+), Cu(2+), Hg(2+), Mn(2+), Ni(2+), Fe(3+), and the sensitivity is about 10(-7)M. The fluorescent changes of H(2)L upon the addition of cations Zn(2+) and triethylamine is utilized as an AND logic gate at the molecular level, using Zn(2+) and triethylamine as chemical inputs and the fluorescence intensity signal as output., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The title Schiff base compound, C(33)H(30)N(4)O(4)·H(2)O, adopts an E configuration with respect to each C=N double bond. In the mol-ecule, there are naphthoxide anions and the protonated imino N atoms. Intra-molecular N-H⋯O hydrogen bonds lead to the formation of approximately planar (maximum deviation 0.029 Å for H atom) six-membered rings.. In the crystal, mol-ecules are linked by O-H⋯O and N-H⋯O hydrogen bonds as well as C-H⋯O contacts, leading to the formation of a three-dimensional network.

In the title compound, [Cu(C(24)H(27)N(4)O(3))]ClO(4), the Cu(II) atom has a distorted square-planar coordination geometry and is surrounded by an N(3)O donor set composed of a secondary amine N, a primary amine H, an imino N and a naphthalen-2-olate O atom. An intra-molecular N-H⋯O hydrogen bond occurs. In the crystal, mol-ecules are held together by inter-molecular N-H⋯O hydrogen bonds, leading to the formation of a three-dimensional network.

A new macrocyclic chemosensor containing two naphthalene fluorophores has been synthesized. The fluorescent properties of this receptor has been studied in the presence of various metal ions such as Na(+), Ag(+), Cr(3+), Mn(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+) and Pb(2+). When increasing concentrations of Zn(2+) ions were introduced, the emission of L was drastically increased (EFE = 4.34). This special change was not observed when other metal ions were used; such highly selective fluorescent response indicates that this receptor can easily discriminate Zn(2+) ions from other similar species. Model calculations at DFT level further suggest the possible interaction mode, and relatively steric position between the host and guest also influence the optical response., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In the title compound, [Cu(C(4)H(12)N(2)O)(2)](NO(3))(2), the central Cu(II) atom has a distorted octa-hedral coordination geometry and is surrounded by four N atoms and two O atoms from the two inversion-related 2-(2-amino-ethyl-amino)-ethanol ligands. In the crystal, mol-ecules are held together by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds, leading to the formation of a three-dimensional network.

In the title compound, C(29)H(25)N(3)O(3), the imine double bond has an E configuration. The dihedral angle between the hy-droxy-phenyl and benzene rings in the imine moiety is 26.95 (9)°, and the dihedral angle between the hy-droxy-phenyl and benzimidazole rings in the other moiety is 14.83 (9)°. These angles are probably limited to small values as a consequence of two strong intra-molecular O-H⋯N hydrogen bonds formed between the hy-droxy groups and the imine and imidazole N atoms. The aliphatic chain linking the two ring systems has a gauche conformation, as reflected in C-C-C-O torsion angle of 70.9 (2)°.