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Two d10 M(II) (M = Cd and Zn) coordination polymers (CPs) with chemical formulas, {[Cd(L1)(NCS)2(H2O)]⋅C2H5OH}n(1), and {[Zn(L1)(NCS)2]⋅C2H5OH⋅0.5H2O}n(2) (L1 = 1,3,5‐tris(4‐pyridylsulfanylmethyl)‐2,4,6‐trimethylbenzene) were synthesized and structurally characterized by single‐crystal x‐ray diffraction method. In compound 1, the coordination environment of Cd(II) ion is distorted octahedral bonded to three nitrogen donors from three L1 ligands located in a facial‐position, two nitrogen donors from NCS− and one water molecule. The L1 acts as a bridge ligand with tris‐monodentate coordination mode in a cis‐cis‐cis structural conformation, connecting the Cd(II) to form a two‐dimensional (2D) zigzag‐like layered metal‐organic frameworks. Adjacent 2D layers are then arranged orderly in an ABAB manner to complete its three‐dimensional (3D) supramolecular architecture. In compound 2, the coordination environment of Zn(II) ion is distorted tetrahedral bonded to two nitrogen donors from two L1 ligands and two nitrogen donors from two NCS− ligands. The L1 acts as a bridge ligand with bis‐monodentate coordination mode in a cis‐cis‐cis structural conformation, connecting the Zn(II) ions to form a one‐dimensional (1D) zigzag‐like polymeric chain. Adjacent chains are arranged orderly in an alternate ABAB manner to generate a 2D framework and then further arranged in an AAA manner to complete its 3D supramolecular architecture. The structural characterization as well as thermal‐stability and solvents de‐/ad‐sorption behavior of 1 and 2 are studied and discussed in details. [ABSTRACT FROM AUTHOR]

The reaction of potassium (aza-15-crown-5)dithiocarbamate (KO4NCS2) and (Me2S)AuCl gave the dinuclear complex [Au(O4NCS2)]2, which underwent structural transformation upon heating to rearrange into the hexanuclear complex [Au(O4NCS2)]6. Under similar reaction conditions, KO4NCS2 reacted with AgNO3 or [Cu(CH3CN)4]ClO4 to give the 1-D coordination polymer [Ag(O4NCS2)]n (1) and the tetranuclear complex [Cu(O4NCS2)]4 (2), respectively. It is noted that upon heating a similar structural transformation process occurs from tetranuclear complex 2 to the octanuclear complex [Cu(O4NCS2)]8 (2′), connected by a weak Cu⋯S contact of 2.846 Å, and it has been isolated and corroborated by powder and single-crystal X-ray diffraction studies as well. Moreover, a variety of MO4NCS2 salts (M = Li+, Na+, K+ and Rb+) were used to react with AgNO3 to construct a series of coordination architectures: [LiAg(O4NCS2)2(μ-H2O)0.5]2 (3), {Na[Ag(O4NCS2)2]}n (4), {K[Ag(O4NCS2)2]}n (5) and {Rb[Ag(O4NCS2)2]}n (6). The smallest Li+ ion only coordinates with four oxygen atoms from the same azacrown ether ring and one H2O molecule, leading to a 1-D hydrogen-bonded chain with another azacrown ether ring for complex 3. The larger Na+ ion coordinates with seven oxygen atoms from two different crown ether rings, leading to a 1-D chain for complex 4. However, the largest K+ and Rb+ ions constitute a 1-D framework, except that each metal ion coordinates with eight oxygen atoms from two different crown ether rings, featuring a 1-D helical chain for complexes 5 and 6. Hence, the different sizes of alkaline metal ions exert a dramatic effect on the structural motifs of complexes 3–6. Remarkably, the dithiocarbamate moieties adopt μ2-bridging ([Au(O4NCS2)]2 and [Au(O4NCS2)]6), μ3- and μ4-bridging (1–2) and chelate forms (3–6) in the structural backbones. [ABSTRACT FROM AUTHOR]

Two d10 M(II) (M = Cd and Zn) coordination polymers (CPs) with chemical formulas, {[Cd(L1)(NCS)2(H2O)]⋅C2H5OH}n(1), and {[Zn(L1)(NCS)2]⋅C2H5OH⋅0.5H2O}n(2) (L1 = 1,3,5‐tris(4‐pyridylsulfanylmethyl)‐2,4,6‐trimethylbenzene) were synthesized and structurally characterized by single‐crystal x‐ray diffraction method. In compound 1, the coordination environment of Cd(II) ion is distorted octahedral bonded to three nitrogen donors from three L1 ligands located in a facial‐position, two nitrogen donors from NCS− and one water molecule. The L1 acts as a bridge ligand with tris‐monodentate coordination mode in a cis‐cis‐cis structural conformation, connecting the Cd(II) to form a two‐dimensional (2D) zigzag‐like layered metal‐organic frameworks. Adjacent 2D layers are then arranged orderly in an ABAB manner to complete its three‐dimensional (3D) supramolecular architecture. In compound 2, the coordination environment of Zn(II) ion is distorted tetrahedral bonded to two nitrogen donors from two L1 ligands and two nitrogen donors from two NCS− ligands. The L1 acts as a bridge ligand with bis‐monodentate coordination mode in a cis‐cis‐cis structural conformation, connecting the Zn(II) ions to form a one‐dimensional (1D) zigzag‐like polymeric chain. Adjacent chains are arranged orderly in an alternate ABAB manner to generate a 2D framework and then further arranged in an AAA manner to complete its 3D supramolecular architecture. The structural characterization as well as thermal‐stability and solvents de‐/ad‐sorption behavior of 1 and 2 are studied and discussed in details. [ABSTRACT FROM AUTHOR]

• Cu(II) coordination polymer and trinickel EMACs were synthesized and structurally characterized using the unsymmetrical pyrazine-modulated Hppza ligand. • Magnetic interaction parameters for 3 (J = −199.2 cm−1) and 4 (J = −178.0 cm−1) support superexchange pathways along metal cores. • Due to the electron-withdrawing effect of pyrazine, the nickel strings of Hppza are readily reduced, retarding oxidation. • The activities of ligands and their nickel string complexes against various proteins were compared with theoretical calculations, and then the ADME/T properties of molecules were examined. • The interactions occurring in the molecular docking calculation were examined in detail with the Protein-Ligand Interaction Profiler (PLIP) service. The unsymmetrical pyrazine-modulated ligand, N-(pyridine-2-yl)pyrazin-2-amine (Hppza) (1), its 1D straight-chain copper (II) coordination polymer [Cu 2 (Hppza) 2 ∙(NO 3) 4 ] n (2) and trinuclear metal string [Ni 3 (µ 3 -ppza) 4 Cl 2 ] (3) and [Ni 3 (µ 3 -ppza) 4 (NCS) 2 ] (4) complexes have been successfully synthesized and structurally characterized. The free ligand Hppza (1) exhibits anti-syn conformation. In an asymmetric unit of 2 , there are two kinds of Cu(II) atoms, both of which have elongated octahedral coordination geometry, and the copper(II) centers are linked by oxygen atoms of one nitrate anion. There are only minor differences in Ni...Ni bond lengths between pyrazine-modulated ligand complexes of [Ni 3 (μ 3 -ppza) 4 × 2 ] (X = Cl− (3), NCS− (4)) and their unmodulated analogs, while the distances between the terminal nickel atoms and the axial ligands 3 and 4 are shorter. The results of magnetic susceptibility measurements showed an antiferromagnetic exchange constant (J) of about J = –199.2 cm–1 for 3 and J = –178.0 cm–1 for 4. The electrochemical properties of nickel strings of Hppza differ significantly from their unmodulated counterparts. The activities of ligands and their metal complexes against various proteins that are AChE (PDB ID: 4M0E), BChE (PDB ID: 5NN0), α-Gly (PDB ID: 1UAS), hCA I (PDB ID: 2CAB), and hCA II (PDB ID: 3DC3) were compared, and then the ADME/T properties of molecules were examined. Afterward, the interactions occurring in the docking calculation were examined in detail with the Protein-Ligand Interaction Profiler (PLIP) service. These complexes were inhibitors of BChE, hCA I and II, α-glycosidase and AChE enzymes for complex 3 and 5 with Ki values of 12.65 and 42.95 μM for hCA I, 3.64 and 15.84 μM for hCA II, 5.44 and 50.07 μM for BChE, 15.85 and 4.77 μM for α-glycosidase and 8.58 and 86.24 μM for AChE, respectively. The unsymmetrical pyrazine-modulated ligand, N-(pyridine-2-yl)pyrazin-2-amine (Hppza) (1), its straight chain copper (II) coordination polymer [Cu 2 (Hppza) 2 (NO 3) 4 ] n (2) and trinickel string complexes [Ni 3 (µ 3 -ppza) 4 Cl 2 ] (3) and [Ni 3 (µ 3 -ppza) 4 (NCS) 2 ] (4) have been successfully synthesized and structurally characterized. The activities of ligands and their metal complexes against various proteins were compared with theoretical calculations, and then the ADME/T properties of molecules were examined. Afterward, the interactions occurring in the docking calculation were examined in detail with the Protein-Ligand Interaction Profiler (PLIP) service. [Display omitted] [ABSTRACT FROM AUTHOR]