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Chemistry (Weinheim An Der Bergstrasse,... Jun 2024The synthesis of a water-soluble, phosphine-pegylated iridium(I) catalyst and its application in hydrogen isotope exchange (HIE) reactions in buffer is reported. The...
The synthesis of a water-soluble, phosphine-pegylated iridium(I) catalyst and its application in hydrogen isotope exchange (HIE) reactions in buffer is reported. The longer polyethylene glycol side chains on the phosphine increased the water solubility independently from the pH. HIE reactions of polar substrates in protic solvents were studied. DFT calculations gave further insides into the catalytic processes. The scope and limitation of the pegylated catalyst was studied in HIE reactions of several complex compounds in borax buffer at pH 9 and the best conditions were applied in a tritium experiment with the drug telmisartan.
PubMed: 38861127
DOI: 10.1002/chem.202402038 -
Chemistry (Weinheim An Der Bergstrasse,... Jun 2024A chromium complex carrying two benzanellated N-heterocyclic phosphenium (bzNHP) ligands was prepared by a salt metathesis approach. Spectroscopic studies suggest that...
A chromium complex carrying two benzanellated N-heterocyclic phosphenium (bzNHP) ligands was prepared by a salt metathesis approach. Spectroscopic studies suggest that the anellation enhances the π-acceptor ability of the NHP-units, which is confirmed by the facile electrochemical reduction of the complex to a spectroscopically characterized radical anion. Co-photolysis with H2 allowed extensive conversion into a σ-H2-complex, which shows a diverse reactivity towards donors and isomerizes under H-H bond fission and shift of a hydride to a P-ligand. The product carrying phosphenium, phosphine and hydride ligands was also synthesized independently and reacts reversibly with CO and MeCN to yield bis-phosphine complexes under concomitant Cr-to-P-shift of a hydride. In contrast, CO2 was not only bound but reduced to give an isolable formato complex, which reacted with ammonia borane under partial recovery of the metal hydride and production of formate. Further elaboration of the reactions of the chromium complexes with CO2 and NH3BH3 allowed to demonstrate the feasibility of a Cr-catalyzed transfer hydrogenation of CO2 to methanol. The various complexes described were characterized spectroscopically and in several cases by XRD studies. Further insights in reactivity patterns were provided through (spectro)electrochemical studies and DFT calculations.
PubMed: 38860887
DOI: 10.1002/chem.202401714 -
ACS Macro Letters Jun 2024Great effort has been dedicated to the engineering of porous organic cages (POCs) in geometry and topology. Yet, harnessing these cage-like entities as premade building...
Great effort has been dedicated to the engineering of porous organic cages (POCs) in geometry and topology. Yet, harnessing these cage-like entities as premade building units to construct infinite cage-based superstructures remains elusive. In this study, we design a type of vertex-modified phosphine organic prism by a postfunctionalized approach and use it as a ditopic cage monomer to achieve an intercage supramolecular polymerization via the synergy of metal coordination and π-π dimerization. The resulting cage-by-cage polymers can further hierarchically organize into superstructures of diverse morphologies and dimensionalities, including 1D fibers, 2D lamellae, and 3D vesicles. Control over the cosolvents is capable of well regulating their structural hierarchies and self-assembled shapes. This would pave a way for the creation of cage-based supramolecular assemblies and nanomaterials.
PubMed: 38856711
DOI: 10.1021/acsmacrolett.4c00317 -
Food Chemistry May 2024Chitosan quaternary phosphine salts (NPCS) were synthesized with enhanced antimicrobial properties using a two-step method. Composite films (CNSP) were prepared by...
Chitosan quaternary phosphine salts (NPCS) were synthesized with enhanced antimicrobial properties using a two-step method. Composite films (CNSP) were prepared by incorporating NPCS and polyvinyl alcohol (PVA) as the base material, citric acid as the crosslinker and functional additive, exhibiting antibacterial and UV-blocking properties. The composite film showed a maximum tensile strength of 20.4 MPa, an elongation at break of 677%, and a UV light barrier transmittance of 70%. Application of these composite membranes in preserving strawberries demonstrated effectiveness in maintaining freshness by preventing water loss, inhibiting microbial growth, and extending shelf life. In addition, the composite film demonstrated biosafety. These results indicate that CNSP composite films holds significant promise for safe and sustainable food packaging applications.
PubMed: 38850971
DOI: 10.1016/j.foodchem.2024.139908 -
Naunyn-Schmiedeberg's Archives of... Jun 2024Inflammatory bowel disease (IBD) is often accompanied by metabolic imbalance, and infliximab (IFX) can alleviate IBD symptoms, but its metabolic mechanisms remain...
Inflammatory bowel disease (IBD) is often accompanied by metabolic imbalance, and infliximab (IFX) can alleviate IBD symptoms, but its metabolic mechanisms remain unclear. To investigate the relationship between IBD, metabolism, and IFX, an acute and chronic ulcerative colitis (UC) model induced by dextran sulfate sodium (DSS) was established. Plasma samples were analyzed using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, followed by multivariate statistical analysis. The results showed that IFX could alleviate colonic shortening and reduce colonic pathological damage in acute and chronic mouse colitis, improve acute and chronic UC, and ameliorate metabolic disturbances. Among the 104 elevated metabolites and 170 decreased metabolites, these metabolites mainly belonged to amino acids, glucose, and purines. The changes in these metabolites were mainly associated with drug metabolism-other enzymes, riboflavin metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phosphonate and phosphinate metabolism, and phenylalanine metabolism. In summary, this study provides a valuable approach to explore the metabolic mechanisms of IFX in treating acute and chronic UC from a metabolomics perspective.
PubMed: 38847830
DOI: 10.1007/s00210-024-03201-9 -
Chemistry (Weinheim An Der Bergstrasse,... Jun 2024P-chiral supramolecular phosphine ligands are crucial for asymmetric transformations, but their synthesis is tedious. We report a one-step synthesis of thermally stable...
P-chiral supramolecular phosphine ligands are crucial for asymmetric transformations, but their synthesis is tedious. We report a one-step synthesis of thermally stable P-chiral supramolecular phosphines and their performance in the asymmetric hydrogenation of functionalized alkenes. A rational designing and synthesis of (R, R)-QuinoxP* ligated palladium complex (Pd-2) in excellent yield is reported. This Pd-2 catalyzed a direct P-C coupling of 2,3-dihydro-1-H-phosphindole (A1)/1,2,3,4-tetrahydrophosphindoline (A2) with 1-(3-iodophenyl)urea/2-iodo (B1)/6-hydroxy pyridine (B2) and, produced corresponding ligands L1-L3. The P-C coupling between A1 and B2 produced 6-(2,3-dihydro-1H-phosphindol-1-yl)pyridine-2(1H)-one (L2) with an excellent enantiomeric excess of up to 99%. L2 was found to be remarkably stable even at 150 °C and did not oxidize/hydrolyze for at least 24 hours in open air. Such thermal stability and an impediment to oxidation are unprecedented. L2 self-assembled and produced L2-C1 (Pt), L2-C2(Pd), and L2-C3(Rh) assemblies. The utility of the self-assembled P-chiral ligand was demonstrated in the Rh-catalyzed asymmetric hydrogenation (AH) of functionalized olefins. The L2-C3 catalyzed AH of functionalized alkenes and delivered chiral products with excellent enantioselectivity of >99%. A small library of 16 substrates was subjected to AH using L2-C3 to produce chiral compounds with excellent conversion and ee.
PubMed: 38845585
DOI: 10.1002/chem.202401077 -
Journal of Nuclear Medicine : Official... Jul 2024Benchtop Mo/Tc and W/Re generators enable economical production of molecular theranostic Tc and Re radiopharmaceuticals, provided that simple, kit-based chemistry exists...
Benchtop Mo/Tc and W/Re generators enable economical production of molecular theranostic Tc and Re radiopharmaceuticals, provided that simple, kit-based chemistry exists to radiolabel targeting vectors with these radionuclides. We have previously described a diphosphine platform that efficiently incorporates Tc into receptor-targeted peptides. Here, we report its application to label a prostate-specific membrane antigen (PSMA)-targeted peptide with Tc and Re for diagnostic imaging and systemic radiotherapy of prostate cancer. Two diphosphine-dipeptide bioconjugates, DP1-PSMAt and DP2-PSMAt, were formulated into kits for radiolabeling with Tc and Re. The resulting radiotracers were studied in vitro, in prostate cancer cells, and in vivo in mouse xenograft models, to assess similarity of uptake and biodistribution for each Tc/Re pair of agents. Both DP1-PSMAt and DP2-PSMAt could be efficiently radiolabeled with Tc and Re using kit-based methods to furnish the isostructural compounds M-DP1-PSMAt and M-DP2-PSMAt (M = [Tc]Tc, [Re]Re). All Tc/Re radiotracers demonstrated specific uptake in PSMA-expressing prostate cancer cells, with negligible uptake in prostate cancer cells that did not express PSMA or in which PSMA uptake was blocked. M-DP1-PSMAt and M-DP2-PSMAt also exhibited high tumor uptake (18-30 percentage injected dose per gram at 2 h after injection), low retention in nontarget organs, fast blood clearance, and excretion predominantly via a renal pathway. Importantly, each pair of Tc/Re radiotracers showed near-identical biologic behavior in these experiments. We have prepared and developed novel pairs of isostructural PSMA-targeting Tc/Re theranostic agents. These generator-based theranostic agents have potential to provide access to the benefits of PSMA-targeted diagnostic imaging and systemic radiotherapy in health care settings that do not routinely have access to either reactor-produced Lu radiopharmaceuticals or PET/CT infrastructure.
Topics: Male; Prostatic Neoplasms; Mice; Rhenium; Animals; Humans; Technetium; Radioisotopes; Cell Line, Tumor; Tissue Distribution; Glutamate Carboxypeptidase II; Antigens, Surface; Radiopharmaceuticals; Theranostic Nanomedicine; Peptides; Precision Medicine
PubMed: 38844360
DOI: 10.2967/jnumed.124.267450 -
Dalton Transactions (Cambridge, England... Jun 2024A rigid pentadentate chelating ligand (HL) has been utilized to synthesize a series of octacoordinate mononuclear complexes, [Dy(L)(PhPO)(OOCR)] (where R = CH (1), C(CH)...
Eight-coordinate mono- and dinuclear Dy(III) complexes containing a rigid equatorial plane and an anisobidentate carboxylate ligand in the axial position: synthesis, structure and magnetism.
A rigid pentadentate chelating ligand (HL) has been utilized to synthesize a series of octacoordinate mononuclear complexes, [Dy(L)(PhPO)(OOCR)] (where R = CH (1), C(CH) (2), CF (3)) and a dinuclear complex, [Dy(L)(PhPO){(OOC)CH}] (4) based on the highly anisotropic Dy(III) ion. All the complexes were structurally characterized by single-crystal X-ray diffraction studies. The complexes were formed by the coordination action of the dianionic pentadentate ligand [L], one phosphine oxide, and carboxylate ligands. DC and AC magnetic measurements were performed on 1-4. Complexes 1-4 show SMM behaviour, under zero DC field for 1 and 4, and under 500 Oe and 1000 Oe DC fields for 2 and 3 respectively, with thermally activated, Raman, and Raman and quantum tunnelling dominant relaxation mechanisms for 1 and 2, 3 and 4, respectively.
PubMed: 38842042
DOI: 10.1039/d4dt00803k -
The Journal of Organic Chemistry Jun 2024Shortwave infrared (SWIR, 1000-1700 nm) absorbing and emitting dyes are needed for infrared diodes and sensors used in a wide variety of industrial and medical...
Shortwave infrared (SWIR, 1000-1700 nm) absorbing and emitting dyes are needed for infrared diodes and sensors used in a wide variety of industrial and medical applications. Herein, an electron-withdrawing phosphine oxide (P═O) substituted xanthene is coupled with strong indolizine donors to produce a SWIR absorbing (λ = 1294 nm in DCM) and emitting (λ = 1450 nm in DCM) dye called . The unique properties of this dye are characterized via photophysical, electrochemical, and computational analyses.
PubMed: 38841830
DOI: 10.1021/acs.joc.4c00741 -
Bioinorganic Chemistry and Applications 2024X-ray crystallography, spectroscopy, computational methods, molecular docking studies, and DNA-binding studies have been useful in the investigations of intermolecular...
Molecular Structure, Spectroscopic, Frontier Molecular Orbital Analysis, Molecular Docking Studies, and DNA-Binding Studies of Osmium(II)-Cymene Complexes with Aryl Phosphine and Aryl Phosphonium Assemblies.
X-ray crystallography, spectroscopy, computational methods, molecular docking studies, and DNA-binding studies have been useful in the investigations of intermolecular and intramolecular interactions of osmium-cymene oxalato complexes with aryl phosphine and aryl phosphonium groups in both primary and secondary coordination spheres, respectively. Molecular structures of the novel complexes PPh[Os(--cymene)Br(--CO)] () and [Os(--cymene) (--CO)PPh] () were resolved by single-crystal X-ray diffraction (XRD). Primary and secondary coordination sphere contacts were investigated using Hirshfeld surface analysis which was supported by molecular docking (MD) studies. The MD data obtained predicted significant differences in binding energy across three receptors for the two osmium complexes. An DNA-binding study was accomplished using UV-Vis spectroscopy which showed that both and bond with DNA through an intercalation approach. The optimized molecular geometry, frontier molecular orbital (E and E) energies, global electrophilicity index (), chemical hardness (), chemical potential (), and the energy band gap (E-E) were calculated utilizing density functional theory (DFT) methods. Computed structural parameters (bond lengths and angles) support the experimental single-crystal XRD data.
PubMed: 38840845
DOI: 10.1155/2024/6697523