75178-90-4Relevant academic research and scientific papers
Design of chiral separation media using monodisperse functionalized macroporous beads: effects of polymer matrix, tether, and linkage chemistry
Lewandowski,Murer,Svec,Frechet
, p. [d]1629-1638 (1998)
Porous size monodisperse methacrylate beads containing amino and hydroxyl groups, which can be used as a platform for the production of chiral separation media, have been prepared using the staged templated suspension polymerization process. The monomers 2-hydroxyethyl methacrylate and several tert-butoxycarbonyl-protected aminoalkyl methacrylates were used for the preparation of both hydroxyl- and amino-functionalized beads. Attachment of a chiral selector based on L-valine-3,5-dimethylanilide through a carbamate and a urea linkage, respectively, provides chiral stationary phases with excellent enantioselectivities in the separation of the enantiomers of 3,5-dinitrobenzamido derivatives of α-amino acids. For comparison purposes, a separation medium was also prepared by the direct polymerization of a chiral monomer analogous to the hydroxyethyl methacrylate-based stationary phase. The chiral stationary phases prepared with the N-methyl-2-aminoethyl methacrylate platform exhibit the best selectivity, and separation factors as high as 15 were achieved under normal-phase HPLC conditions.
Stereoselective synthesis of hydroxypyrrolidines and hydroxypiperidines by cyclization of γ-oxygenated-α,β-unsaturated sulfones
Carretero, Juan Carlos,Arrayas, Ramon Gomez,De Gracia, Isabel Storch
, p. 3379 - 3382 (1996)
cis and trans 2,3-disubstituted pyrrolidines and piperidines have been prepared stereoselectively by intramolecular conjugate addition of N-substituted γ-oxygenated-α,β-unsaturated phenyl sulfones. The best cis-selectivities were obtained from the alcohols and the best trans-selectivities from the OTIPS derivatives.
The synthesis and evaluation of novel sialic acid analogues bound to matrices for the purification of sialic acid-recognising proteins
Abo, Samia,Ciccotosto, Silvana,Alafaci, Annette,Von Itzstein, Mark
, p. 201 - 208 (1999)
A novel N-acetylneuraminic acid analogue, 2-S-(5'-aminopentyl) 5-acetamido-3,5-dideoxy-2-thio-D-glycero-α-D-galacto-2-nonulopyranosidonic acid, as well as the thiosialoside 2-S-(2'-aminoethyl) 5-acetamido-3,5-dideoxy-2-thio-D-glycero-α-D-galacto-2-nonulopyranosidonic acid, have been synthesised and successfully coupled to CNBr-activated Sepharose 4B through the terminal amino group. The resultant affinity resins have proved efficient in purifying a number of sialic acid-recognising proteins such as Vibrio cholerae sialidase, sialidase-L from leech, trans-sialidase from Trypanosoma cruzi, and sialyltransferases from rat liver, all in high yield. Copyright (C) 1999 Elsevier Science Ltd.
Membrane Phospholipid Analogues as Molecular Rulers to Probe the Position of the Hydrophobic Contact Point of Lysophospholipid Ligands on the Surface of G-Protein-Coupled Receptor during Membrane Approach
Aoki, Junken,Inoue, Asuka,Ohwada, Tomohiko,Otani, Yuko,Sayama, Misa,Sekijima, Masakazu,Uwamizu, Akiharu
, p. 1173 - 1201 (2020)
When lipid mediators bind to G-protein-coupled receptors (GPCRs), the ligand first enters the lipid bilayer, then diffuses laterally in the cell membrane to make hydrophobic contact with the receptor protein, and finally enters the receptor's binding pock
Oxetanyl peptides: Novel peptidomimetic modules for medicinal chemistry
McLaughlin, Martin,Yazaki, Ryo,Fessard, Thomas C.,Carreira, Erick M.
, p. 4070 - 4073 (2014)
The synthesis of novel oxetanyl peptides, where the amide bond is replaced by a non-hydrolyzable oxetanylamine fragment, is reported. This new class of pseudo-dipeptides with the same H-bond donor/acceptor pattern found in proteins expands the repertoire
A catalyCEST MRI contrast agent that detects the enzyme-catalyzed creation of a covalent bond
Hingorani, Dina V.,Randtke, Edward A.,Pagel, Mark D.
, p. 6396 - 6398 (2013)
CatalyCEST MRI can detect enzyme activity by employing contrast agents that are detected through chemical exchange saturation transfer (CEST). A CEST agent, Tm-DO3A-cadaverine, has been designed to detect the catalytic activity of transglutaminase (TGase), which creates a covalent bond between the agent and the side chain of a glutamine amino acid residue. CEST appeared at -9.2 ppm after TGase conjugated Tm-DO3A-cadaverine to albumin, which also caused a decrease in CEST from albumin at +4.6 ppm. Studies with model peptides revealed similar appearances and decreases in detectable CEST effects following TGase-catalyzed conjugation of the contrast agent and peptide. The MR frequencies and amplitudes of these CEST effects were dependent on the peptide sequence, which demonstrated the sensitivity of CEST agents to ligand conformations that may be exploited to create more responsive molecular imaging agents. The chemical exchange rates of the substrates and conjugated products were measured by fitting modified Bloch equations to CEST spectra, which demonstrated that changes in exchange rates can also be used to detect the formation of a covalent bond by catalyCEST MRI.
The influence of fluorocarbon chain and phosphorylcholine on the improvement of hemocompatibility: A comparative study in polyurethanes
Tan, Dongsheng,Li, Zhen,Yao, Xuelin,Xiang, Chunlan,Tan, Hong,Fu, Qiang
, p. 1344 - 1353 (2014)
To study the influence of fluorinated surfaces and biomimetic surfaces on the improvement of the blood compatibility of polymers, three monomers containing a fluorinated tail and/or phosphorylcholine groups were designed and synthesized, and were then introduced into polyurethanes based on 4,4′-diphenylmethane diisocyanate (MDI), poly(tetramethylene glycol) (PTMG) and 1,4-butanediol (BDO) via end-capping. The bulk and surface characterization of the polyurethanes was carried out by dynamic mechanical analysis (DMA), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopic analysis (XPS), atomic force microscope (AFM), and water contact angle measurements. The results indicate that the fluorocarbon chains can drive the phosphorylcholine groups to aggregate at the surface of polyurethane, and the two components show spontaneous arrangement to adapt to the environment when in contact with water. The preliminary evaluation of hemocompatibility was carried out via fibrinogen adsorption and platelet adhesion. The fluorocarbon chains and phosphorylcholine groups showed a synergistic effect on the improvement of hemocompatibility.
Multivalent assembly of a pyrene functionalized thio-N-acetylglucosamine: Synthesis, spectroscopic and WGA binding studies
Montenegro, Hugo O.,Di Chenna, Pablo H.,Spagnuolo, Carla C.,Uhrig, María Laura
, p. 6 - 12 (2019)
We introduce here a new fluorescent derivative of 1-thio-β-N-acetylglucosamine linked to a pyrene system through a triazolylpentyl spacer, designed to self-assemble into a multivalent glycocluster. The synthesis was achieved by efficient CuAAC click reaction between a pyrene functionalized with an azide group and a suitable alkynyl thiomonosaccharide. Spectroscopic studies by fluorometry indicated that the self-assembly in aqueous medium is modulated by concentration and pH changes, the latter due to the presence of the amino group close to the π system. Circular dichroism experiments revealed a moderate positive signal, suggesting that the pyrene-thioGlcNAc conjugate can aggregate into a chiral supramolecular assembly. The sugar moiety showed to specifically and reversibly interact with the wheat germ agglutinin, a fact that was demonstrated by turbidity assay. SEM microscopy of a lyophilized solution at pH 10 revealed a fibrillar morphology compatible with the presence of tubular micelles, whereas crystalline and amorphous solids are formed at lower pHs.
BIOMIMETIC G-QUARTET COMPOUNDS
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Paragraph 0155-0156; 0160-0164, (2021/10/11)
The invention relates to a compound of formula I: wherein - A is present or absent; - X1, X2, X3 and X4 are, independently from each other, an alkyl; - Y1, Y2, Y3 and Y4 are independently from each other a C1-C10 alkyl, - Z1, Z2, Z3 and Z4 are independently from each other a C1-C5 linear alkyl; - R1 is a group allowing to carry out bioorthogonal reactions; and - R2 is group comprising a N.
Synthetic Mimics of Native Siderophores Disrupt Iron Trafficking in Acinetobacter baumannii
Banas, Victoria S.,Bohac, Tabbetha J.,Fang, Luting,Giblin, Daryl E.,Wencewicz, Timothy A.
, p. 2138 - 2151 (2021/07/07)
Many pathogenic bacteria biosynthesize and excrete small molecule metallophores, known as siderophores, that are used to extract ferric iron from host sources to satisfy nutritional need. Native siderophores are often structurally complex multidentate chelators that selectively form high-affinity octahedral ferric iron complexes with defined chirality recognizable by cognate protein receptors displayed on the bacterial cell surface. Simplified achiral analogues can serve as synthetically tractable siderophore mimics with potential utility as chemical probes and therapeutic agents to better understand and treat bacterial infections, respectively. Here, we demonstrate that synthetic spermidine-derived mixed ligand bis-catecholate monohydroxamate siderophores (compounds 1-3) are versatile structural and biomimetic analogues of two native siderophores, acinetobactin and fimsbactin, produced by Acinetobacter baumannii, a multidrug-resistant Gram-negative human pathogen. The metal-free and ferric iron complexes of the synthetic siderophores are growth-promoting agents of A. baumannii, while the Ga(III)-complexes are potent growth inhibitors of A. baumannii with MIC values 1 μM. The synthetic siderophores compete with native siderophores for uptake in A. baumannii and maintain comparable apparent binding affinities for ferric iron (KFe) and the siderophore-binding protein BauB (Kd). Our findings provide new insight to guide the structural fine-tuning of these compounds as siderophore-based therapeutics targeting pathogenic strains of A. baumannii.
