2752-17-2Relevant articles and documents
A New Manganese(III) Complex from Bis(5-methylsalicylaldehyde)-3-oxapentane-1,5-diamine: Synthesis, Characterization, Antioxidant Activity and Luminescence
Wu, Huilu,Wang, Cuiping,Wang, Fei,Peng, Hongping,Zhang, Han,Bai, Yuchen
, p. 1028 - 1034 (2015)
A Schiff base ligand bis(5-methylsalicylaldehyde)-3-oxapentane-1,5-diamine (H2L) has been prepared. Reaction of the shape-specific designed ligand with MnAc2 afforded a new complex, namely, [Mn2L2Ac2] 1. The ligand and complex 1 were characterized by physic-chemical and spectroscopic methods. The crystal structure of complex 1 has been determined by single-crystal X-ray diffraction. It reveals a centrosymmetric binuclear neutral entity, in which Mn(III) ion is bridged by two ligand L and six-coordinated with the coordination surround of distorted octahedron geometry. The antioxidant activities of the ligand and complex 1 were in vitro determined by superoxide and hydroxyl radical scavenging methods, which indicates that the complex 1 exhibits better scavenging activity of hydroxyl radical and superoxide radical than the ligand. Moreover, under the excitation at room temperature, luminescence studies have been carried out on solution-state samples. The result of their fluorescence properties shows that the strong and characteristic luminescence for the ligand and complex. The complex 1 exhibited intense shift in the fluorescence band compare to the ligand attributed to the coupled effect of the metal and the ligand.
A convenient preparation of diamino oligoethylene glycols and amino polyethylene glycols
Yinglin,Tianbao,Hongwen,Xiao
, p. 79 - 84 (1991)
Diamino oligoethylene glycols and amino polyethylene glycols were prepared in good yields by using the reaction of sodium diformamide with oligoethylene glycol or polyethylene glycol dichlorides or ditosylates followed by hydrolysis using ethanolic hydrochloride.
Lower ligand denticity leading to improved thermodynamic and kinetic stability of the Gd3+ complex: The strange case of OBETA
Baranyai, Zsolt,Botta, Mauro,Fekete, Marianna,Giovenzana, Giovanni B.,Negri, Roberto,Tei, Lorenzo,Platas-Iglesias, Carlos
, p. 7680 - 7685 (2012)
OBETA, OBETA, you bet: Thermodynamic and kinetic measurements show an apparent paradox. The stability of complexes of lanthanide trivalent ions is higher with the heptadentate ligand OBETA (ethylene glycol-bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic aci
Chemical Promiscuity of Non-Macrocyclic Multidentate Chelating Ligands for Radiometal Ions: H4neunpa-NH2vs H4noneunpa
Wharton, Luke,Kurakina, Elena,Radchenko, Valery,Schaffer, Paul,Orvig, Chris
supporting information, p. 4076 - 4092 (2021/04/07)
A comparative investigation of two structurally related potentially nonadentate chelating ligands, H4neunpa-NH2 and H4noneunpa, has been undertaken to examine the influence of bifunctionalization on their coordination chemistry and metal ion selectivity. Significantly improved synthetic routes for each compound have been developed, employing straightforward high-yielding strategies. Radiolabeling studies with [44Sc]Sc3+, [111In]In3+, [177Lu]Lu3+, and [225Ac]Ac3+ revealed a sharp contrast between the affinity of each chelator for large radiometal ions. H4noneunpa demonstrated highly effective coordination of [177Lu]Lu3+ and [225Ac]Ac3+ achieving quantitative radiochemical yields (>98%) at ligand concentrations of 10-6 M (room temperature (RT), 10 min), with excellent stability when challenged in human serum, while H4neunpa-NH2 was unable to complex either metal ion effectively. Nuclear magnetic resonance (NMR) spectroscopy was employed to explore the coordination chemistry of each chelating ligand with nonradioactive metal ions, spanning a range of ionic radii and coordination numbers. A comprehensive conformational analysis of each metal complex was undertaken using density functional theory (DFT) calculations to explore the coordination geometries and explain the discrepancy in binding characteristics. Theoretical simulations revealed notable differences in the coordination geometry and apparent denticity of each ligand, which together account for the observed selectivity in metal binding and have important implications for the future design of complexes based upon this framework to target large radiometal ion coordination.
Bivalent HIV-1 fusion inhibitors based on peptidomimetics
Kobayakawa, Takuya,Ebihara, Kento,Tsuji, Kohei,Kawada, Takuma,Fujino, Masayuki,Honda, Yuzuna,Ohashi, Nami,Murakami, Tsutomu,Tamamura, Hirokazu
, (2020/11/07)
Membrane fusion is a valid target for inhibition of HIV-1 replication. A 34-mer fragment peptide (C34), which is contained in the HIV-1 envelope protein gp41, has significant anti-HIV activity. Previously, a dimeric derivative of C34 linked by a disulfide bridge at its C-terminus was found to have more potent anti-HIV activity than the C34 peptide monomer. To date, several peptidomimetic small inhibitors have been reported, but most have lower potency than peptide derivatives related to C34. In the present study we applied this dimerization concept to these peptidomimetic small inhibitors and designed several bivalent peptidomimetic HIV-1 fusion inhibitors. The importance of the length of linkers crosslinking two peptidomimetic compounds was demonstrated and several potent bivalent inhibitors containing tethered peptidomimetics were produced.
A novel graphite-like stacking structure in a discrete molecule and its molecular recognition behavior
Akine, Shigehisa,Onuma, Takahiro,Nabeshima, Tatsuya
supporting information, p. 9369 - 9372 (2018/06/18)
A graphite-like stacking structure was nicely reproduced in a discrete molecule that was prepared by 2+2 macrocyclic Schiff base formation. In the crystal structure, two hexabenzocoronene planes are closely stacked with displacement, yielding the intramolecular stacking structure similar to an AB- or ABC-stacking pattern in natural graphite. This molecule showed a recognition ability toward electron-deficient aromatic molecules in solution.
