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• A stable 3D Co(II)-based coordination polymer was synthesized and characterized. • The solvent stability test was conducted in various common organic solvents. • The cytotoxicity was evaluated by MTT assays against HEK-293 cell line. • This polymer showed significant antibacterial activity against the investigated strains. • This polymer recognized as a desirable antibacterial agent. The current work reports the facile synthesis and complete characterization of a stable 3D Co(II)-based coordination polymer, namely Co(HCOO) 2 (4,4′-bpy) (1), (4,4′-bpy=4,4′-bipyridine), prepared via two different synthetic methods including solvothermal reaction and reflux method. The Co-coordination polymer was fully characterized by 1H NMR, FT-IR, FE-SEM, TGA, ICP, BET, single-crystal X-ray crystallography, powder X-ray diffraction crystallography, and VSM analysis. The cell treatment with Co-coordination polymer was evaluated, and the cytotoxicity study was done by MTT assays against the HEK-293 cell line. Furthermore, the antibacterial properties of Co-coordination polymer nanoparticles were investigated. The Co-coordination polymer showed significant antibacterial properties against the selected strains of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. A stable 3D Co(II)-based coordination polymer, Co(HCOO) 2 (4,4′-bpy), was synthesized via two facile different synthetic methods, including solvothermal reaction and reflux method. It was fully characterized and the cytotoxicity was evaluated by MTT assays against HEK-293 cell line. The Co-coordination polymer showed significant antibacterial activity against the strains of Gram-negative and Gram-positive bacteria. The antibacterial properties of this polymer are due to a combination of physicochemical properties such as solubility, shape, size and specific surface area. [Display omitted] [ABSTRACT FROM AUTHOR]

• Cooperative assemblies of methanesulfonamide containing benzohydrazides. • Noncovalent interactions were investigated experimentally and computationally. • Hirshfeld surface analysis revealed the role of noncovalent contacts in X-ray packing. • The energetic features of NCIs were characterized by DFT calculations. • MEP, QTAIM and NCIPlot computational tools rationalized the structural assemblies. • Compound 6 showed 13-fold superior inhibition than thiourea. The significant involvement of noncovalent interactions in catalyst design and synthesis of materials provides a fundamental impetus to explore various synthons that produce complex frameworks. Therefore, in the present work, cooperative assemblies of two methanesulfonamide containing benzohydrazide derivatives (6 and 7) were designed and analyzed. These compounds were synthesized through a straightforward approach using hydrazide 3 and 4-methyl-2-acetylthiophene (4) and 4-methoxyacetophenone (5) in refluxing ethanol. Both compounds were characterized by FTIR, NMR, LCMS and X-ray crystallography. Noncovalent interactions such as C H...π interactions and hydrogen bonding played a crucial and dominant role in the structural design of complex molecular architectures. X-ray crystal analysis reveals the presence of an intramolecular classical N H...O strong hydrogen bond and a weaker C H...O interaction in compounds 6 and 7. The N H...O arrangement of hydrazone-hydrazone cores also facilitates a C H...π close contact between the sulfonamide methyl group and the proximal benzoyl aromatic ring. Moreover, the methoxy group in 7 is also involved in C H...O/S and C H...π interactions. Hirshfeld surface analysis further revealed the involvement of these noncovalent contacts in the stabilization of molecular topology of both compounds. The energetic features of noncovalent interactions were characterized by DFT calculations while molecular electrostatic potential (MEP), QTAIM and NCIPlot computational tools rationalized the structural assemblies found in the crystal packing of both compounds. Furthermore, the biological assessment against urease enzyme revealed 13-fold superior inhibition with an IC 50 value of 1.67 ± 0.19 µM for compound 6. In vitro inhibitory data was complemented with an in silico modeling where the observed interactions between the active site amino acids and compound 6 underscored the importance of heteroaryl (thienyl) component for strong inhibitory effects. Finally, the assessment of pharmacokinetic parameters proposed compound 6 as a suitable druggable inhibitor for further evaluation. QTAIM and NCIPlot analysis of the dimer exhibiting CH 3 ...π interactions in compound 6. [Display omitted] [ABSTRACT FROM AUTHOR]

• Synthesis of pyrazoloquinoline scaffold in excellent yield. • Unraveling the synergistic effects of C-H...O, C-H...N, Cl...O, π...π, Cl...π and CH...π interactions. • Evaluation of energetic features using Hirshfeld analysis and DFT calculations. • Characterization of π-stacking and halogen bonding interactions using QTAIM and NCIPlot methods. • Assessment of urease inhibitory potential using indophenol method. The present study investigates the influence of noncovalent interactions in the design and structural control of crystal packing of pyrazoloquinoline derivative. Compound 3 was prepared in a two-step process in excellent yield. The reaction of 2,7-dichloroquinoline-3-carbaldehyde (1) and hydrazine monohydrate gave access to intermediate 2 which was alkylated regioselectively at the N1 pyrazole nitrogen. The synergistic effects of noncovalent interactions such as H-bonding (C-H...O, C-H...N), halogen bonding (Cl...O) and π-contacts (π...π, Cl...π and CH...π) remained crucial in leading the structural topology of pyrazoloquinoline skeleton. The types of noncovalent interactions was energetically evaluated using Hirshfeld analysis and DFT calculations. The π-stacking and halogen bonding contacts have been studied using QTAIM and NCIPlot techniques. The pharmacological evaluation of compound 3 as anti-urease agent revealed considerably strong potency (IC 50 = 8.51 ± 0.10 µM) when compared with positive control, thiourea. In vitro inhibitory data were confirmed through molecular modeling investigation where several key binding interactions were revealed between pyrazoloquinoline and vital residues inside the binding pocket of urease enzyme. ADME investigation successfully predicted various pharmacokinetic properties satisfying the druggable criteria and presenting the title compound to act as a lead inhibitor of Jack bean urease for further investigations. [Display omitted] QTAIM and NCIPlot for the π-stacked dimer (a) and HB/XB dimer (b) in compound 3. The combination of π-interactions (π...π, Cl...π and CH...π) is evidenced by the NCIplot analysis. The existence of the XB and another one connecting one CH group to the negative belt of the Cl-atom is also confirmed. [ABSTRACT FROM AUTHOR]

A new coordination compound [HgL(ClO 4) 2 EtOH] (1) was fabricated from a mixture of Hg(NO 3) 2 and NaClO 4 with 1,2-diphenyl-1,2-bis((phenyl-(pyridin-2-yl)methylene)hydrazono)ethane (L). Complex 1 exhibits a mononuclear heteroleptic discrete structure, where the ligand L adopts a helical twist conformation. The Hg(II) cation is N 4 O 3 coordinated by four nitrogen atoms from L and by three oxygen atoms from two monocoordinated ClO 4 – anions and one ethanol molecule. The crystal structure is stabilized by the intermolecular O–H⋯O hydrogen bonds, and Cl–O⋯π Ph and C–H⋯π Ph interactions. The long Hg–N/O bonds have been analyzed in terms of coordination, semicoordination or spodium bonds using QTAIM and NCIplot index computational tools. [Display omitted] • [HgL(ClO 4) 2 EtOH] (1) was fabricated from a mixture of Hg(NO 3) 2 and NaClO 4 with L. • L stands for 1,2-diphenyl-1,2-bis((phenyl-(pyridin-2-yl)methylene)hydrazono)ethane. • Complex 1 exhibits a mononuclear heteroleptic discrete structure. • L adopts a helical twist conformation. In this work we have synthesized and characterized a new coordination compound [HgL(ClO 4) 2 EtOH] (1), fabricated from a mixture of Hg(NO 3) 2 and NaClO 4 with 1,2-diphenyl-1,2-bis((phenyl-(pyridin-2-yl)methylene)hydrazono)ethane (L). Single-crystal X-ray crystallography revealed the formation of a mononuclear heteroleptic discrete structure with one molecule [HgL(ClO 4) 2 EtOH] in the asymmetric unit. The ligand L adopts a helical twist conformation. The Hg(II) cation is coordinated by four nitrogen atoms from L and by three oxygen atoms from two monocoordinated ClO 4 – anions and one ethanol molecule. The crystal structure of 1 is stabilized by the intermolecular O–H⋯O hydrogen bonds, and Cl–O⋯π Ph and C–H⋯π Ph interactions, yielding a supramolecular 3D framework. Moreover, the long Hg–N/O bonds have been analyzed in terms of coordination, semicoordination or spodium bonds using QTAIM and NCIplot index computational tools. [ABSTRACT FROM AUTHOR]

• Group 14 γ-effect. • Silicon pyridinium ions. • Homo-hyperconjugation. • Percaudal interaction. The γ-effect of the group 14 metals is a stabilizing interaction involving the back-lobe of the σ C-M (M = Si, Ge, Sn, Pb) interacting with the developing carbocation γ to the tetrel. This percaudal interaction has been observed in solvolysis experiments with significant rate enhancements over unsubstituted systems, and subsequent isolation of three-membered ring products. In this study, the γ-effect is experimentally investigated in the solid phase with X-ray crystallography, the solution phase with Si-C coupling constants, and the gas phase via collision-induced dissociation (CID). Moving from 2- and 4-silylethyl substituted pyridines to the more electron demanding substituted pyridinium ion systems results in systematic shifts in key structural parameters including the 29Si-13C NMR coupling constants consistent with the cyclopropane-like resonance form attributable to the γ-effect. However, these shifts are much less in magnitude than those previously reported for the well documented β-effect. The gas phase CID results also reflect this with the fragmentation pathways for the silylethyl substituted systems not being dominated by the percaudal interaction, compared to previous studies where all major fragments were attributable to the β-effect. Density functional theory (DFT) calculated hyperhomodesmotic equations in combination with natural bond orbital (NBO) theory also supported the experimental trends with the γ-effect providing stabilization in the pyridinium ion systems studied, but to a much smaller extent to the β-effect. [Display omitted] [ABSTRACT FROM AUTHOR]

This work reports on synthesis and in-depth structural investigations on new mixed cobalt(II)/cobalt(III) heteroleptic paramagnetic porous metal–organic framework of the salt-like structure {[(CoIIIL 2) 2 CoII(NCS) 2 ][CoII(NCS) 4 ]} n ∙ a (solvent) (1 ∙ a (solvent)), obtained from the reaction of Co(NCS) 2 with 2-pyridinecarbaldehyde isonicotinoylhydrazone (HL). [Display omitted] • Complex {[(CoIIIL 2) 2 CoII(NCS) 2 ][CoII(NCS) 4 ]} n ∙ a (solvent) (1 ∙ a (solvent)) is reported. • 2-pyridinecarbaldehyde isonicotinoylhydrazone was used as a parent ligand HL. • Complex 1 ∙ a (solvent) is paramagnetic. • 1 ∙ a (solvent) is stable after drying at 80 °C for several days, yielding complex 1. • Adsorption properties of 1 and HL at different temperatures were determined. We report on a mixed cobalt(II)/cobalt(III) heteroleptic coordination polymer of the salt-like structure {[(CoIIIL 2) 2 CoII(NCS) 2 ][CoII(NCS) 4 ]} n ∙ a (solvent) (1 ∙ a (solvent)), obtained by a reaction of Co(NCS) 2 with 2-pyridinecarbaldehyde isonicotinoylhydrazone (HL). Complex 1 ∙ a (solvent) contains 15.52% of solvent molecules, which fits to six molecules of EtOH per one [(CoIIIL 2) 2 CoII(NCS) 2 ][CoII(NCS) 4 ] species, and the structure of the crystals can be assigned to the {[(CoIIIL 2) 2 CoII(NCS) 2 ][CoII(NCS) 4 ]} n ∙6EtOH composition. 1 ∙ a (solvent) was found to be stable after drying at 80 °C for several days, yielding a solvent-free complex 1. The FTIR data of both structures supports the complete loss of solvents after drying, while the general framework remains intact. As evident from the comparison of the experimental X-ray powder diffraction data of 1 with the calculated powder pattern generated from the single crystal X-ray data of 1 ∙ a (solvent), the former complex partially loses its crystallinity; however, the experimental powder pattern resembles the calculated one. Thus, the overall structure of 1 is similar to that of 1 ∙ a (solvent). The crystal structure of 1 ∙ a (solvent) is constructed from the V-shaped (CoIIIL 2)+ cations, where the metal ion is N 4 S 2 -coordinated by two L. These (CoIIIL 2)+ cations are interlinked through CoII(NCS) 2 molecules by coordination via free 4-pyridyl nitrogen atoms, yielding a 1D polymeric cationic chain {[(CoIIIL 2) 2 CoII(NCS) 2 ]2+} n , which are interlinked into a 3D framework through a bunch of bifurcated (N)C–S⋯π(2-Py) and linear (NN)C–H⋯O non-covalent interactions. Due to such 3D aggregation, a half of rhombohedral cells are filled by the interlayered [CoII(NCS) 4 ]2– anions, while the other half of cells is free from non-volatile species and filled with volatile solvent molecules, yielding 1D tubular voids, which occupy about 17% of unit cell volume. Direct current variable-temperature magnetic susceptibility measurements on a polycrystalline sample of 1 ∙ a (solvent) were carried out in the temperature range 1.8–300 K. The magnetic behaviour of 1 ∙ a (solvent) indicates the presence of magnetic anisotropy of the CoII ions and/or very weak intermolecular exchange interactions. The surface and pore properties of 1 and HL were calculated by N 2 adsorption at 77 K. In addition, CO 2 adsorption properties of 1 and HL at different temperatures were determined. It was found that 1 increased both textural and CO 2 adsorption properties. [ABSTRACT FROM AUTHOR]