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1. Correlating magnetic anisotropy with [Mo(CN) ₇ ] ⁴⁻ geometry of Mn ^II –Mo ^III magnetic frameworks

   https://doi.org/10.1039/c9dt02164g  

   Magott, Michał; Dunbar, Kim R.; Pinkowicz, Dawid (January 2019, Dalton Transactions)

   Four new three-dimensional (3-D) coordination frameworks based on the heptacyanomolybdate( iii ) anion were prepared and characterised by magnetic measurements: {[Mn II (imH) 2 ] 2 [Mn II (H 2 O)(imH) 3 ][Mn II (imH) 4 ] [Mo III (CN) 7 ] 2 ·6H 2 O} n ( 1 ) (imH = imidazole), {[Mn II (H 2 O) 2 (imH)] 3 [Mn II (H 2 O)(imH) 2 ][Mo III (CN) 7 ] 2 ·5H 2 O} n ( 2 ), {[Mn II (Htrz)(H 2 O) 2 ][Mn II (Htrz) 0.7 (H 2 O) 2.3 ][Mo III (CN) 7 ]·5.6H 2 O} n ( 3 ) (Htrz = 1,2,4-triazole) and {[Mn II (H 2 O) 2 ] 3 [Mn II (H 2 O) 4 ][Mo III (CN) 7 ] 2 ·6H 2 O·2urea} n ( 4 ). All four compounds exhibit long-range ferrimagnetic ordering and exhibit an opening of their magnetic hysteresis loops at 1.8 K; 1 and 2 exhibit the highest coercive fields among all known [Mo III (CN) 7 ]-based assemblies, 5000 and 4500 Oe respectively. The coercivity of 1–4 is correlated with the geometry of the heptacyanomolybdate( iii ) anion and the cyanide bridging pattern. A paramagnetic analogue of compound 1 , {[Mn II (imH) 2 ] 2 [Mn II (H 2 O)(imH) 3 ][Mn II (imH) 4 ][Re III (CN) 7 ] 2 ·6H 2 O} n ( 1Re ), where the heptacyanomolybdate( iii ) anion is substituted by the diamagnetic heptacyanorhenate( iii ) anion is also reported which constitutes the first example of a coordination framework based on [Re III (CN) 7 ] 4− . 

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2. Copper(I) SNS pincer complexes: Impact of ligand design and solvent coordination on conformer interconversion from spectroscopic and computational studies

   Lynn, M.A.; Miecznikowski, J.R.; Jasinski, J.P.; Kaur, M.; Mercado, B.Q.; Reinheimer, E.; Almanza, E.; Kharbouch, R.M.; Smith, M.R.; Zygmont, S.E.; et al (September 2019, Inorganica Chimica Acta)

   The syntheses and detailed characterizations (X-ray crystallography, NMR spectroscopy, cyclic voltammetry, infrared spectroscopy, electrospray mass spectrometry, and elemental analyses) of two new Cu(I) pincer complexes are reported. The pincer ligand coordinates through one nitrogen and two sulfur donor atoms and is based on bis-imidazole or bis-triazole precursors. These tridentate SNS ligands incorporate pyridine and thione-substituted imidazole or triazole functionalities with connecting methylene units that provide flexibility to the ligand backbone and enable high bite-angle binding. Variable temperature 1H NMR analysis of these complexes and of a similar zinc(II) SNS system shows that all are fluxional in solution and permits the determination of delta G double dagger and delta S double dagger. DFT calculations are used to model the fluxionality of these complexes and indicate that a coordinating solvent molecule can promote hemilability of the SNS ligand by lowering the energy barrier involved in the partial rotation of the methylene units. 

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3. Di-triazole boat conformation leads to metal–organic nanotube while chair conformation leads to coordination polymer

   https://doi.org/10.1039/D3CE00835E  

   Nalaoh, Phattananawee; Jenkins, David M (September 2023, CrystEngComm)

   Aliphatic-cored di-1,2,4-triazole ligands form both a metal–organic nanotube (MONT) and a coordination polymer upon reaction with silver nitrate. 

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4. Synthesis of 1,2,3-triazole containing compounds as potential antimicrobial agents

   https://doi.org/10.7717/peerj-ochem.10  

   Bezold, Elise L; Kempton, Robert J; Green, Keith D; Hensley, Ramey W; Gilliam, Olivia K; Garneau-Tsodikova, Sylvie; Onorato, Amber J (July 2024, PeerJ Organic Chemistry)

   Invasive fungal infections are increasing worldwide due to an expanding number of immunocompromised patients as well as an increase in drug-resistant fungi. While fungal resistance has increased, this resistance has not been accompanied by the development of new antifungals. A common class of antifungal agents that are prescribed are the azoles, which contain either a triazole or an imidazole group. Unfortunately, current azoles, like fluconazole, have been shown to be less effective with the increase in resistant fungal pathogens. Therefore, the development of novel azole antifungal compounds is of urgent need. The objective of this research was to synthesize triazole-containing small molecules with potent antifungal activity. The scaffold of the synthesized compounds contains a triazole moiety and was synthesized via a copper-catalyzed azide-alkyne click reaction (CuAAC) between the appropriate alkyne and azide intermediates. The minimum inhibitory concentrations of these compounds were determined using standard broth microdilution assays against opportunistic bacteria and fungi associated with life-threatening invasive fungal infections. Although the synthesized compounds possessed no antimicrobial activity, these results can be used to further the long-term goal of developing and optimizing lead compounds with potentin vitroantifungal activity. 

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5. Photoresponsive Zn ²⁺ -specific metallohydrogels coassembled from imidazole containing phenylalanine and arylazopyrazole derivatives

   https://doi.org/10.1039/d0dt01809k  

   Sallee, Ashanti; Ghebreyessus, Kesete (August 2020, Dalton Transactions)

   null (Ed.)

   Stimuli-responsive supramolecular gels and metallogels have been widely explored in the past decade, but the fabrication of metallogels with reversible photoresponsive properties remains largely unexplored. In this study, we report the construction of photoresponsive hybrid zinc-based metallohydrogel systems coassembled from an imidazole functionalized phenylalanine derivative gelator (ImF) and carboxylic acid functionalized arylazopyrazole (AzoPz) molecular photoswitches in the presence of Zn 2+ ions. Unlike traditional covalent conjugation, noncovalent introduction of small molecular switches into the gel matrix provides a convenient route to generate photoresponsive functional materials with tunable properties and expands the scope of optically controlled molecular self-assemblies. It has been found that the carboxylic acid functionalized AzoPz derivatives alone or mixed with the ImF moiety could not self-assemble to form any gels. However, in the presence of Zn 2+ ions they readily formed the coassembled hybrid metallogels in an alkaline aqueous solution with various morphologies. These results suggest that the gelation process was triggered by the Zn 2+ ions. In addition, the ImF gelator shows specific response to Zn 2+ ions only. The presence of the AzoPz moiety in the gel matrix makes the metallogel coassemblies photoresponsive and the reversible gel-to-sol phase transition was studied by UV-vis spectroscopy. The gels showed a slow reversible light-induced gel-to-sol phase transition under UV ( λ = 365 nm) and then sol-to-gel transition by green light ( λ = 530) irradiation resulting in the reformation of the original gel state. The morphology and viscoelastic properties of the fibrillar opaque metallogels have been characterized by transmission electron microscopy (TEM) and rheological measurement, respectively. 

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