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A combination of N,N',N"-tris(3-pyridyl)-1,3,5-benzenetricarboxamide (L1) and p-chlorobenzoic acid (HL2) with Zn(NO3)2·6H2O resulted in the formation of a dinuclear metallacycle [ZnL1(L2)2(DMF)2]2 (1(DMF)4). In 1(DMF)4, the Zn(II) centre adopts a square pyramidal geometry, while one of the pyridyl N out of the three pyridyl groups in L1 remained uncoordinated. Solvated DMF molecules are present in 1(DMF)4. The structural and chemical nature of 1(DMF)4 is effective for it to act as a potential fluorescent probe for the detection of nitroaromatic compounds. It is observed that the probe, 1(DMF)4, could selectively detect picric acid (PA) among various aromatic compounds in solution (DMSO), while the solid state (contact mode) detection showed a positive sensing response for the nitrophenols (PA: 87% quenching efficiency, 2,4-dinitrophenol (2,4-DNP): 57% quenching efficiency and 4-nitrophenol (4-NP): 40% quenching efficiency). The limit of detection (LOD) of PA by the probe in DMSO was found to be 6.8 × 10-11 M while the LOD in contact mode detection was estimated to be 0.49 ng cm-2. The mechanism of selective detection of PA by 1(DMF)4 in DMSO was analyzed through photophysical studies, 1H-NMR experiments and also by density functional theory (DFT) calculations. The effective overlap of the absorption spectrum of 1(DMF)4 and emission spectrum of PA in DMSO suggests that the Förster resonance energy transfer (FRET) is responsible for quenching phenomena in DMSO. The DFT calculations and molecular docking studies showed the adduct formation due to the favorable interactions between 1(DMF)4 and PA in DMSO, while negligible interactions were observed between 1(DMF)4 with other aromatic compounds. The experimental and DFT studies showed that the efficient sensing ability of PA by 1(DMF)4 in the solid-state was due to photoelectron transfer (PET) and FRET phenomena described herein. [ABSTRACT FROM AUTHOR]

This work presents synthesis and characterization of two cobalt‐based coordination polymers (CPs) prepared by using two positionally related pyridine‐2,6‐dicarboxamide fragment‐based ligands containing appended arylcarboxylic acid groups. While arylcarboxylate groups of ligands coordinate to the Co(II) ions to produce 2D CPs; the amidic N−H groups remain free and generate large cavities lined with hydrogen bonds. Such hydrogen bonding cavities based CPs were found to reversibly adsorb molecular iodine. The Lewis acidic Co(II) ions and metal‐coordinated labile solvent molecules in CPs promoted noteworthy heterogeneous catalysis for Friedel crafts reactions as well as multicomponent condensation reactions. [ABSTRACT FROM AUTHOR]

This article discusses the design principles and strategies and the structural outcome of various supramolecular architectures constructed by utilizing well‐defined coordination complexes as the metalloligands. We have included selected examples of metalloligands, offering either pyridyl or arylcarboxylic acid groups as the appended functional groups, for illustrating the construction of their supramolecular architectures. Both geometrical position and the number of the appended functional groups emerging from a metalloligand were found to critically regulate the structural aspects and dimensionality of the resultant material. The article concludes by delineating the structure‐directing lessions as well as the potential applications of the metalloligand‐based supramolecular architectures for the generation of next‐level materials. [ABSTRACT FROM AUTHOR]

Hydrogen bonding plays significant roles in various biological processes during substrate orientation and binding and therefore assists in assorted organic transformations. However, replicating the intricate selection of hydrogen bonds, as observed in nature, in synthetic complexes has met with only limited success. Despite this fact, recent times have seen the emergence of several notable examples where hydrogen bonds have been introduced in synthetic complexes. A few such examples have also illustrated the substantial role played by the hydrogen bonds in influencing and often controlling the catalytic outcome. This perspective presents selected examples illustrating the significance of hydrogen bonds offered by the coordination and the organometallic complexes that aid in providing the desired orientation to a substrate adjacent to a catalytic metal center and remarkably assisting in the catalysis. [ABSTRACT FROM AUTHOR]

This perspective presents the design, synthesis and crystal structures of a large number of architectures constructed using assorted metalloligands of pyridine-2,6-dicarboxamide based ligands. The metalloligands offered various appended functional groups, whereas design strategies included varying both their position and number. A combination of these parameters resulted in the development of assorted architectures including discrete trinuclear and tetranuclear complexes as well as 1D/2D/3D coordination polymers. The metalloligand strategy not only assisted in the construction of ordered crystalline materials with varied dimensionalities but also judiciously allowed the incorporation of Lewis acidic and redox-active secondary metals in the resultant architectures. As a result, such designer architectures illustrated their noteworthy role both as homogenous and heterogeneous catalysts in different organic transformation reactions. [ABSTRACT FROM AUTHOR]

We present two ZnII‐ and CdII‐based coordination polymers (CPs), L‐Zn and L‐Cd, offering H‐bonding‐based cavities of varying dimensions. Both CPs were used for the highly selective detection of S2O72− and Fe3+ ions where H‐bonding based cavities played an important role. Fluorescence quenching, competitive binding studies and binding parameters substantiated significant recognition of S2O72− and Fe3+ ions by both CPs. [ABSTRACT FROM AUTHOR]

Keywords: Metalloligands; Pyridyl; Carboxylic acid; Coordination Polymers; Architectures EN Metalloligands Pyridyl Carboxylic acid Coordination Polymers Architectures 1 1 1 11/11/22 20221101 NES 221101 The Front Cover shows the design principles and strategies and the structural outcome of various supramolecular architectures constructed by utilizing well-defined coordination complexes as the metalloligands. Cover Picture: Tailored Inorganic-Organic Architectures via Metalloligands (Chem. Rec. 11/2022) Metalloligands, Pyridyl, Carboxylic acid, Coordination Polymers, Architectures. [Extracted from the article]

Thiosemicarbazones are known for their biological and pharmacological activities. In this study, we have synthesized and characterized 3-Methoxybenzaldehyde thiosemicarbazone (3-MBTSc) and 4-Nitrobenzaldehyde thiosemicarbazone (4-NBTSc) using IR, 1HNMR and 13C NMR. The compound's in vitro anticancer activities against different cell lines were evaluated. Molecular docking, Insilco ADMET, and drug-likeness prediction were also done. The test compounds showed a comparative IC50 and growth inhibition with the standard drug Doxorubicin. The IC50 ranges from 2.82 µg/mL to 14.25 µg/mL in 3-MBTSc and 2.80 µg/mL to 7.59 µg/mL in 4-NBTSc treated cells. The MTT assay result revealed, 3-MBTSc inhibits 50.42 and 50.31 percent of cell growth in B16-F0 and EAC cell lines, respectively. The gene expression showed that tumor suppressor genes such as PTEN and BRCA1 are significantly upregulated in 7.42 and 5.33 folds, and oncogenes, PKC, and RAS are downregulated −7.96 and −7.64 folds, respectively in treated cells. The molecular docking performed on the four targeted proteins (PARP, VEGFR-1, TGF-β1, and BRAFV600E) indicated that both 4-NBTSc and 3-MBTSc potentially bind to TGF-β1 with the best binding energy of −42.34 Kcal/mol and −32.13 Kcal/mol, respectively. In addition, the test compound possesses desirable ADMET and drug-likeness properties. Overall, both 3-MBTSc and 4-NBTSc have the potential to be multitargeting drug candidates for further study. Moreover, 3-MBTSc showed better activity than 4-NBTSc. [ABSTRACT FROM AUTHOR]

We present two Zn II - and Cd II -based coordination polymers (CPs), L-Zn and L-Cd, offering H-bonding-based cavities of varying dimensions. Both CPs were used for the highly selective detection of S 2 O 7 2- and Fe 3+ ions where H-bonding based cavities played an important role. Fluorescence quenching, competitive binding studies and binding parameters substantiated significant recognition of S 2 O 7 2- and Fe 3+ ions by both CPs., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)