Publications by authors named "Clarkson G"

A novel nickel-based metal organic framework (MOF) [Ni(FDC)(CHOH)(HO)](HO) (UOW-6) utilizing biomass-derived 2,5-furan dicarboxylate (FDC) as a ligand is reported as an electrocatalyst for anodic ethylene glycol (EG) oxidation with cathodic hydrogen evolution. The MOF structure was analyzed using single crystal X-ray-diffraction, thermogravimetric analysis (TGA) and thermodiffractometry, to establish its structure and verify phase purity. The material was dropcast on carbon fiber paper as a catalyst, and by using a three-electrode system, UOW-6 requires only 1.

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Article Synopsis
  • Cyclic peptides are important for drug development, but their synthesis can be challenging.
  • The 3-aminoazetidine (3-AAz) subunit enhances the synthesis of small head-to-tail cyclic peptides, improving cyclization of various peptide lengths.
  • Additionally, the 3-AAz allows for further modifications of the macrocyclic peptides, enabling the creation of tagged compounds like dyes and biotin.
  • XRD analysis shows that the azetidine structure promotes a stable, all-trans conformation and boosts resistance against proteases.
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Photoactive prodrugs offer potential for spatially-selective antitumour activity with minimal effects on normal tissues. Excited-state chemistry can induce novel effects on biochemical pathways and combat resistance to conventional drugs. Photoactive metal complexes in particular, have a rich and relatively unexplored photochemistry, especially an ability to undergo facile intersystem crossing and populate triplet states.

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Purpose: To describe social media online grief supports, accessing behaviors, psychosocial variables, and feelings of support among individuals grieving the loss of a child aged <18 years.

Method: This online survey study recruited 26 adults grieving the loss of a child using social media. Dependent variables included feelings of support and frequency of access.

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On the basis of steric hindrance, one carbonyl group in a diketone can be reduced in a regioselective manner, with high enantioselectivity. The methodology can be extended to ketones with varied length of hydrocarbon chain spacing, and the products can be converted by oxidation to hydroxy esters or lactones without loss of enantiopurity.

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Biphenyl-fused-dioxacyclodecynes are a promising class of strained alkyne for use in Cu-free 'click' reactions. In this paper, a series of functionalised derivatives of this class of reagent, containing fluorescent groups, are described. Studies aimed at understanding and increasing the reactivity of the alkynes are also presented, together with an investigation of the bioconjugation of the reagents with an azide-labelled protein.

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Grieving individuals experience changes in cognitive function. The purpose of this study was to examine factors that are associated with a decline in cognitive function in grieving adults. Questionnaires for sleep, depression, anxiety, self-efficacy to manage emotions, and cognitive function were completed.

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In this study, we report the synthesis and characterization of some heteroleptic Cr(III) complexes of the form [Cr(Phen)L](OTf), where Phen = 1,10-phenanthroline and L is either 2,2'-bipyridine (bpy) or its derivatives, such as 4,4'-dimethyl-2,2'-bipyridine (4,4'-DMB), 4,4'-dimethoxy-2,2'-bipyridine (4,4'-DMOB), 4,4'-di-butyl-2,2'-bipyridine (4,4'-dbpy), 5,5'-dimethyl-2,2'-bipyridine (5,5'-DMB), 4,4'-dimethoxycarbonyl-2,2'-bipyridine (4,4'-dmcbpy) or 1,10-phenanthroline derivatives, such as 5-methyl-1,10-phenanthroline (5-Me-Phen) and 4,7-dimethyl-1,10-phenanthroline (4,7-DMP). Heteroleptic complexes were prepared in two stages the intermediate [Cr(Phen)(CFSO)](CFSO) and five examples have been crystallographically characterized. Steady-state absorption and luminescence emission characteristics of these complexes were measured in 1 M HCl solutions.

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Background: COVID-19-associated visitor restrictions altered parents' involvement in their infant's care in the neonatal intensive care unit (NICU).

Purpose: The purpose of this article is to explore how restrictions affected parents' perceptions of experience in the NICU and to build a conceptual model of communication flow during times of crisis.

Methods: This qualitative study was set in a level III 52-bed NICU.

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Hypoxia represents a remarkably exploitable target for cancer therapy, is encountered only in solid human tumors, and is highly associated with cancer resistance and recurrence. Here, a hypoxia-activated mitochondria-accumulated Ru(II) polypyridyl prodrug functionalized with conjugated azo (Az) and nitrogen mustard (NM) functionalities, RuAzNM, is reported. This prodrug has multimodal theranostic properties toward hypoxic cancer cells.

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An efficient methodology for the synthesis of benzofuropyridines and dibenzofurans from fluoropyridines or fluoroarenes and 2-bromophenyl acetates is reported. This streamlined one-pot procedure consists of a four-step directed -lithiation, zincation, Negishi cross-coupling, and intramolecular nucleophilic aromatic substitution, allowing for the facile assembly of a diverse set of fused benzofuro heterocycles.

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Rollover cyclometalated complexes constitute a family of derivatives which differ from classical cyclometalated species in certain aspects. Various potential application fields have been developed for both classes of compounds, which have both similarities and differences. In order to uncover the relationships and distinctions between these two families of compounds, four Pt(II) cyclometalated complexes derived from 2-phenylpyridine (ppy) and 2,2'-bipyridine (bpy), assumed as prototypical ligands, were compared.

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CO epoxidation to cyclic carbonates under mild, solvent-free conditions is a promising pathway toward sustainable CO utilization. Metal-organic frameworks (MOFs) explored for such applications so far are commonly composed of nonrenewable ligands such as benzene dicarboxylate (BDC) or synthetically complex linkers and therefore are not suitable for commercial utilization. Here, we report new yttrium 2,5-furandicarboxylate (FDC)-based MOFs: "UOW-1" and "UOW-2" synthesized via solvothermal assembly, with the former having a unique structural topology.

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The synthesis of a range of N-(heterocyclesulfonyl)-functionalised Noyori-Ikariya catalysts is described. The complexes were prepared through a short sequence from C2-symmetric 1,2-diphenylethylene-1,2-diamine (DPEN) and were characterised by a range of methods including X-ray crystallography. The complexes were active catalysts for the asymmetric transfer hydrogenation (ATH) of a range of acetophenone derivatives, giving products of high ee in most cases, with notably good results for -substituted acetophenones.

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We have synthesized a series of novel substituted sulfonyl ethylenediamine (en) Ru arene complexes 1-8 of [(η-arene)Ru(R-SO-EnBz)X], where the arene is benzene, HO(CH)O-phenyl or biphenyl (biph), X = Cl or I, and R is phenyl, 4-Me-phenyl, 4-NO-phenyl or dansyl. The 'piano-stool' structure of complex 3, [(η-biph)Ru(4-Me-phenyl-SO-EnBz)I], was confirmed by X-ray crystallography. The values of their aqua adducts were determined to be high (9.

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The synthesis of three coordination polymers of cerium(III) and the ligand pyridine-2,4,6-tricarboxylate (PTC) is reported. Two of the materials crystallise under hydrothermal conditions at 180 °C, with [Ce(PTC)(HO)]·1.5HO, (1), being formed on extended periods of reaction time, 3 days or longer, and Ce(PTC)(HO), (2), crystallising after 1 day.

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The asymmetric transfer hydrogenation (ATH) of α-keto-1,4-diamides using a tethered Ru/TsDPEN catalyst was achieved in high ee. Studies on derivatives identified the structural elements which lead to the highest enantioselectivities in the products. The α-keto-amide reduction products have been converted to a range of synthetically valuable derivatives.

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We report the synthesis of the organo-osmium anticancer complex [Os(η--cym)(,-azpy-NMe)Br]PF (1) containing natural abundance Os (1.96%), and isotopically-enriched (98%) [Os]-1. Complex 1 and [Os]-1 contain a π-bonded -cymene (-cym), a chelated 4-(2-pyridylazo)-,-dimethylaniline (azpy-NMe), and a monodentate bromide as ligands.

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Complexes trans,trans,trans-[Pt(N3)2(OH)(OCOR)(py)2] where py = pyridine and where OCOR = succinate (1); 4-oxo-4-propoxybutanoate (2) and N-methylisatoate (3) have been synthesized by derivation of trans,trans,trans-[Pt(OH)2(N3)2(py)2] (4) and characterised by NMR and EPR spectroscopy, ESI-MS and X-ray crystallography. Irradiation of 1-3 with green (517 nm) light initiated photoreduction to Pt(ii) and release of the axial ligands at a 3-fold faster rate than for 4. TD-DFT calculations showed dissociative transitions at longer wavelengths for 1 compared to 4.

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-Methylene-β-lactams were synthesized in two steps from commercially available 3-bromo-2-(bromomethyl)propionic acid and reacted with arene diazonium salts in a Heck-type arylation in the presence of catalytic amounts of Pd(OAc) under ligand-free conditions. The products, arylidene-β-lactams, were obtained in high yields as single isomers. The β-hydride elimination step of the Pd-catalyzed coupling reaction proceeds with high -regioselectivity and -stereoselectivity.

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Organometallic complexes with novel activation mechanisms are attractive anticancer drug candidates. Here, we show that half-sandwich iodido cyclopentadienyl iridium(iii) azopyridine complexes exhibit potent antiproliferative activity towards cancer cells, in most cases more potent than cisplatin. Despite their inertness towards aquation, these iodido complexes can undergo redox activation by attack of the abundant intracellular tripeptide glutathione (GSH) on the chelated azopyridine ligand to generate paramagnetic intermediates, and hydroxyl radicals, together with thiolate-bridged dinuclear iridium complexes, and liberate reduced hydrazopyridine ligand.

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Photoactivatable agents offer the prospect of highly selective cancer therapy with low side effects and novel mechanisms of action that can combat current drug resistance. 1,8-Naphthalimides with their extended π system can behave as light-harvesting groups, fluorescent probes and DNA intercalators. We conjugated N-(carboxymethyl)-1,8-naphthalimide (gly-R-Nap) with an R substituent on the naphthyl group to photoactive diazido Pt complexes to form t,t,t-[Pt(py) (N ) (OH)(gly-R-Nap)], R=H (1), 3-NO (2) or 4-NMe (3).

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Background: Water supply limits agricultural productivity of many crops including lettuce. Identifying cultivars within crop species that can maintain productivity with reduced water supply is a significant challenge, but central to developing resilient crops for future water-limited climates. We investigated traits known to be related to water-use efficiency (WUE) and yield in lettuce, a globally important leafy salad crop, in a recombinant inbred line (RIL) lettuce mapping population, produced from a cross between the cultivated Lactuca sativa L.

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Several palladium(ii) and platinum(ii) complexes (1-20) of general formula [M(L)(X)(Y)] [M = Pd, X = Y = Cl (1-Cl-4-Cl), X = Y = OAc (1-OAc-4-OAc); M = Pt: X = Y = Cl (5-8); M = Pd, X = Cl, Y = CH (9-12); M = Pt, X = Cl, Y = CH (13-16) or X = Y = CH (17-20); n = 1-4] have been synthesized by reaction of different Pd(ii) and Pt(ii) derivatives with various 3-substituted 1-(2-pyridyl)-imidazo[1,5-a]pyridines; i.e.L = 1-(2-pyridyl)-3-arylimidazo[1,5-a]pyridine (aryl = Phenyl, L; 2-o-Tolyl, L; Mesityl, L) and 1-(2-pyridyl)-3-benzylimidazo[1,5-a]pyridine (L).

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