23601-40-3Relevant articles and documents
Effect of the length of polyoxyethylene substituents on luminescent bimetallic lanthanide bioprobes
Deiters, Emmanuel,Song, Bo,Chauvin, Anne-Sophieu,Vandevyver, Caroline D. B.,Buenzli, Jean-Claude G.
, p. 1140 - 1152 (2008)
The new homoditopic ligand H2LC2′ self-assembles with lanthanide ions (LnIII) to yield neutral bimetallic helicates of overall composition [Ln2(L C2′)3]; it is fitted with two hexakis(oxyethylene) chains to test their effects on the thermodynamic, photophysical and biochemical properties of these complexes, with particular emphasis on their uptake by living cells. At physiological pH and under stoichiometric conditions, the conditional stability constants log β23 are around 28 resulting in the speciation of the EuIII helicate being >92% for a total ligand concentration of 1 mM. The ligand triplet state features adequate energy (0-phonon transition at ≈800 cm-1) for sensitising the luminescence of EuIII (Q = 19%) and TbIII (Q = 10%) in aerated water at pH 7.4. The Eu(5D0) emission spectrum and lifetime (2.43 ms) are characteristic of a species with pseudo-D3 symmetry and without bound water in the inner coordination sphere. The viability of HeLa cancerous cells is unaffected when incubated with up to 500 μM [Eu2(LC2′)3] during 24 h. The Eu III helicate permeates into the cytoplasm of these cells by endocytosis and remains essentially undissociated, despite a low intracellular concentration of 0.28 μM. In addition, the leakage of the EuIII helicate out of HeLa cells is very minimal over long periods of time. With respect to similar complexes with ligands bearing shorter tris(oxyethylene) chains, no substantial changes are observed, which opens the way for targeting experiments. This study also demonstrates that the [Ln2(L CX)3] helicates are fairly robust entities since their core is unaffected by the substitution in the pyridine 4-position. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Self-Assembly and Molecular Recognition in Water: Tubular Stacking and Guest-Templated Discrete Assembly of Water-Soluble, Shape-Persistent Macrocycles
Wang, Qiuhua,Zhong, Yulong,Miller, Daniel P.,Lu, Xiaoxing,Tang, Quan,Lu, Zhong-Lin,Zurek, Eva,Liu, Rui,Gong, Bing
supporting information, p. 2915 - 2924 (2020/02/04)
Supramolecular chemistry in aqueous media is an area with great fundamental and practical significance. To examine the role of multiple noncovalent interactions in controlled assembling and binding behavior in water, the self-association of five water-soluble hexakis(m-phenylene ethynylene) (m-PE) macrocycles, along with the molecular recognition behavior of the resultant assemblies, is investigated with UV-vis, fluorescence, CD, and NMR spectroscopy, mass spectrometry, and computational studies. In contrast to their different extents of self-aggregation in organic solvents, all five macrocycles remain aggregated in water at concentrations down to the micromolar (μM) range. CD spectroscopy reveals that 1-F6 and 1-H6, two macrocycles carrying chiral side chains and capable of H-bonded self-association, assemble into tubular stacks. The tubular stacks serve as supramolecular hosts in water, as exemplified by the interaction of macrocycles 1-H6 and 2-H6 and guests G1 through G4, each having a rod-like oligo(p-phenylene ethynylene) (p-PE) segment flanked by two hydrophilic chains. Fluorescence and 1H NMR spectroscopy revealed the formation of kinetically stable, discrete assemblies upon mixing 2-H6 and a guest. The binding stoichiometry, determined with fluorescence, 1H NMR, and ESI-MS, reveals that the discrete assemblies are novel pseudorotaxanes, each containing a pair of identical guest molecules encased by a tubular stack. The two guest molecules define the number of macrocyclic molecules that comprise the host, which curbs the "infinite" stack growth, resulting in a tubular stack with a cylindrical pore tailoring the length of the p-PE segment of the bound guests. Each complex is stabilized by the action of multiple noncovalent forces including aromatic stacking, side-chain H-bonding, and van der Waals interactions. Thus, the interplay of multiple noncovalent forces aligns the molecules of macrocycles 1 and 2 into tubular stacks with cylindrical inner pores that, upon binding rod-like guests, lead to tight, discrete, and well-ordered tubular assemblies that are unprecedented in water.
AMYLOID TARGETING AGENTS AND METHODS OF USING THE SAME
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Paragraph 0840, (2018/12/04)
Provided herein is the design and synthesis of novel molecular rotor fluorophores useful for detection of amyloid or amyloid like proteins. The fluorophores are designed to exhibit enhanced fluorescence emission upon associating with amyloid or amyloid like proteins as compared to unbound compound. Also disclosed herein are methods for treating diseases associated with amyloid or amyloid like proteins.
Facially Amphipathic Glycopolymers Inhibit Ice Recrystallization
Graham, Ben,Fayter, Alice E. R.,Houston, Judith E.,Evans, Rachel C.,Gibson, Matthew I.
supporting information, p. 5682 - 5685 (2018/05/09)
Antifreeze glycoproteins (AFGPs) from polar fish are the most potent ice recrystallization (growth) inhibitors known, and synthetic mimics are required for low-temperature applications such as cell cryopreservation. Here we introduce facially amphipathic glycopolymers that mimic the three-dimensional structure of AFGPs. Glycopolymers featuring segregated hydrophilic and hydrophobic faces were prepared by ring-opening metathesis polymerization, and their rigid conformation was confirmed by small-angle neutron scattering. Ice recrystallization inhibition (IRI) activity was reduced when a hydrophilic oxo-ether was installed on the glycan-opposing face, but significant activity was restored by incorporating a hydrophobic dimethylfulvene residue. This biomimetic strategy demonstrates that segregated domains of distinct hydrophilicity/hydrophobicity are a crucial motif to introduce IRI activity, which increases our understanding of the complex ice crystal inhibition processes.
