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101.
Crystals of N,O-diacetyl-5-p-chloranilino-4-hydroxypenta-2,4-dienal, the degradation product from a Stenhouse salt, belong to the monoclinic space groupP21/c witha = 10.845,b = 17.607,c = 8.056 Å, = 95.87 ° andZ = 4. The structure was solved by the heavy-atom method from intensity data measured out to 1.14 Å–1 with CuK radiation. Hydrogen atoms were not located. A finalR of 0.098 for the 549 observed terms was attained. The molecule is in thetrans-trans conformation, and the non-hydrogen atoms in the pentadienal chain and N-acetyl group are almost co-planar. Thep-chloraniline and O-acetyl groups lie on the same side of the pentadienal skeleton, and their respective planes are approximately parallel and at right angles to the plane of the chain. The molecules in the crystal structure are held together by van der Waals' interactions. 相似文献
102.
Angus S. Mackay Joshua W. C. Maxwell Max J. Bedding Dr. Sameer S. Kulkarni Dr. Stephen A. Byrne Lucas Kambanis Dr. Mihai V. Popescu Prof. Robert S. Paton Assoc. Prof. Lara R. Malins Dr. Anneliese S. Ashhurst Dr. Leo Corcilius Prof. Richard J. Payne 《Angewandte Chemie (International ed. in English)》2023,62(50):e202313037
Mild strategies for the selective modification of peptides and proteins are in demand for applications in therapeutic peptide and protein discovery, and in the study of fundamental biomolecular processes. Herein, we describe the development of an electrochemical selenoetherification (e-SE) platform for the efficient site-selective functionalization of polypeptides. This methodology utilizes the unique reactivity of the 21st amino acid, selenocysteine, to effect formation of valuable bioconjugates through stable selenoether linkages under mild electrochemical conditions. The power of e-SE is highlighted through late-stage C-terminal modification of the FDA-approved cancer drug leuprolide and assembly of a library of anti-HER2 affibody conjugates bearing complex cargoes. Following assembly by e-SE, the utility of functionalized affibodies for in vitro imaging and targeting of HER2 positive breast and lung cancer cell lines is also demonstrated. 相似文献
103.
104.
Renfrow MB Mackay CL Chalmers MJ Julian BA Mestecky J Kilian M Poulsen K Emmett MR Marshall AG Novak J 《Analytical and bioanalytical chemistry》2007,389(5):1397-1407
IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis. In IgAN, IgA1 molecules with incompletely galactosylated
O-linked glycans in the hinge region (HR) are present in mesangial immunodeposits and in circulating immune complexes. It is
not known whether the galactose deficiency in IgA1 proteins occurs randomly or preferentially at specific sites. We have previously
demonstrated the first direct localization of multiple O-glycosylation sites on a single IgA1 myeloma protein by use of activated ion-electron capture dissociation (AI-ECD) Fourier
transform ion cyclotron resonance (FT-ICR) tandem mass spectrometry. Here, we report the analysis of IgA1 O-glycan heterogeneity by use of FT-ICR MS and liquid chromatography FT-ICR MS to obtain unbiased accurate mass profiles of
IgA1 HR glycopeptides from three different IgA1 myeloma proteins. Additionally, we report the first AI-ECD fragmentation on
an individual IgA1 O-glycopeptide from an IgA1 HR preparation that is reproducible for each IgA1 myeloma protein. These results suggest that future
analysis of IgA1 HR from IgAN patients and normal healthy controls should be feasible. 相似文献
105.
106.
Ross S. Harvey Emily G. Mackay Lukas Roger Prof. Michael N. Paddon‐Row Prof. Michael S. Sherburn Dr. Andrew L. Lawrence 《Angewandte Chemie (International ed. in English)》2015,54(6):1795-1798
The first total synthesis of the ramonanin family of lignan natural products is described. The short synthesis involves a 2,5‐diaryl‐3,4‐dimethylene tetrahydrofuran intermediate, which participates in an unexpectedly facile Diels–Alder dimerization, generating all four natural products. Insights into the reactivity and stereoselectivity of the key dimerization are provided through computational studies employing B3LYP/6‐31G(d) and M06‐2X/6‐31G(d) model chemistries. 相似文献
107.
Geraldo DA Duran-Lara EF Aguayo D Cachau RE Tapia J Esparza R Yacaman MJ Gonzalez-Nilo FD Santos LS 《Analytical and bioanalytical chemistry》2011,400(2):483-492
Polyamidoamine (PAMAM) dendrimers and water-soluble 3-mercaptopropionic acid (MPA)-capped CdSe quantum dots (QDs) were combined
to produce a new gel containing supramolecular complexes of QDs/PAMAM dendrimers. The formation of the QDs/PAMAM supramolecular
complexes was confirmed by high resolution electron microscopy and Fourier transform infrared (FTIR) analyses. Molecular dynamics
simulations corroborated the structure of the new QDs/PAMAM-based supramolecular compound. Finally, on the basis of the prominent
fluorescent properties of the supramolecular complexes, PAMAM dendrimer was functionalized with folic acid to produce a new
QDs/PAMAM-folate derivative that showed an efficient and selective performance as a marker for gastric cancer cells. 相似文献
108.
109.
Given a cotriple 𝔾 = (G, ε, δ) on a category X and a functor E:X Opp→A into an abelian category A, there exists the cohomology theory of Barr and Beck: Hn(X, E) ε |A| (n ≥ 0, X ε |X|), ([1], p.249). Almost all the important cohomology theories in mathematics have been shown to be special instances of such a general theory (see [1], [2] and [3]). Usually E arises from an abelian group object Y in X in the following manner: it is the contravariant functor from X into the category Ab of abelian groups that associates to each object X in X the abelian group X(X, Y) of maps from X to Y. In such a situation we shall write Hn(X, Y)𝔾 instead of Hn(X, E)G. Barr and Beck [2] have shown that the Eilenberg-MacLane cohomology groups H?n(π, A), n ≥ 2, can be re-captured as follows. One considers the free group cotriple 𝔾′ on the category Gps of groups, which induces in a natural manner a cotriple 𝔾 on the category (Gps, π) of groups over a fixed group π. 相似文献
110.
High-strength, healable, supramolecular polymer nanocomposites 总被引:1,自引:0,他引:1
Fox J Wie JJ Greenland BW Burattini S Hayes W Colquhoun HM Mackay ME Rowan SJ 《Journal of the American Chemical Society》2012,134(11):5362-5368
A supramolecular polymer blend, formed via π-π interactions between a π-electron rich pyrenyl end-capped oligomer and a chain-folding oligomer containing pairs of π-electron poor naphthalene-diimide (NDI) units, has been reinforced with cellulose nanocrystals (CNCs) to afford a healable nanocomposite material. Nanocomposites with varying weight percentage of CNCs (from 1.25 to 20.0 wt %) within the healable supramolecular polymeric matrix have been prepared via solvent casting followed by compression molding, and their mechanical properties and healing behavior have been evaluated. It is found that homogeneously dispersed films can be formed with CNCs at less than 10 wt %. Above 10 wt % CNC heterogeneous nanocomposites were obtained. All the nanocomposites formed could be rehealed upon exposure to elevated temperatures although, for the homogeneous films, it was found that the healing rate was reduced with increasing CNC content. The best combination of healing efficiency and mechanical properties was obtained with the 7.5 wt % CNC nanocomposite which exhibited a tensile modulus enhanced by as much as a factor of 20 over the matrix material alone and could be fully rehealed at 85 °C within 30 min. Thus it is demonstrated that supramolecular nanocomposites can afford greatly enhanced mechanical properties relative to the unreinforced polymer, while still allowing efficient thermal healing. 相似文献