128238-44-8Relevant articles and documents
Chemoenzymatic synthesis of artificial glycopolypeptides containing multivalent sialyloligosaccharides with a γ-polyglutamic acid backbone and their effect on inhibition of infection by influenza viruses
Ogata, Makoto,Murata, Takeomi,Murakami, Kouki,Suzuki, Takashi,Hidari, Kazuya I.P.J.,Suzuki, Yasuo,Usui, Taichi
, p. 1383 - 1393 (2007)
Highly water-soluble, artificial glycopolypeptides with a γ-polyglutamic acid (γ-PGA) backbone derived from Bacillus subtilis sp. and multivalent sialyloligosaccharide units have been chemoenzymatically synthesized as potential polymeric inhibitors of infection by bird and human influenza viruses. 5-Trifluoroacetamidopentyl β-N-acetyllactosaminide and 5-trifluoroacetamidopentyl β-lactoside were enzymatically synthesized from LacNAc and lactose, respectively, by cellulase-mediated condensation with 5-trifluoroacetamido-1-pentanol. After deacetylation, the resulting 5-aminopentyl β-LacNAc and β-lactoside glycosides were coupled to the α-carboxyl groups of the γ-PGA side chains. The artificial glycopolypeptides carrying LacNAc and lactose were further converted to Neu5Acα2-(3/6)Galβ1-4Glcβ and Neu5Acα2-(3/6)Galβ1-4GlcNAcβ sialyloligosaccharide units by α2,3- and α2,6-sialyltransferase, respectively. The interaction of these glycopolypeptides with various influenza virus strains has been investigated by three different methods. Glycopolypeptides carrying Neu5Acα2,6LacNAc inhibited hemagglutination mediated by influenza A and B viruses, and their relative binding affinities for hemagglutinin were 102- to 104-fold higher than that of the naturally occurring fetuin control. A glycopolypeptide carrying Neu5Acα2,6LacNAc inhibited infection by A/Memphis/1/71 (H3N2) 93 times more strongly than fetuin, as assessed by cytopathic effects on virus-infected MDCK cells. The avian virus [A/duck/Hong kong/4/78 (H5N3)] bound strongly to Neu5Acα2,3LacNAc/Lac-carrying glycopolypeptides, whereas the human virus [A/Memphis/1/71 (H3N2)] bound to Neu5Acα2,6LacNAc in preference to Neu5Acα2,6Lac. Taken together, these results indicate that the binding of viruses to terminal sialic acids is markedly affected by the structure of the asialo portion, in this case either LacNAc or lactose, in the sugar chain of glycopolypeptides.
Rapid Synthesis of Bicyclic N-Heterocyclic Cores from N-Terminal α,β-Unsaturated Diazoketones
Santiago, Jo?o Victor,Burtoloso, Antonio C. B.
, p. 2822 - 2830 (2018/06/04)
A method for the synthesis of bicyclic N-heterocyclic cores from N-terminal α,β-unsaturated diazoketones has been developed. The transformation involves three sequential steps that include N-deprotection, an intramolecular aza-Michael, and a photochemical Wolff rearrangement as a one-pot protocol. By using this strategy, a series of substituted bicyclic N-heterocycles, particularly, indolizidines and pyrrolizidines, were synthesize in good yields.
METHOD FOR DETERMINATION OF RECOGNITION SPECIFICITY OF VIRUS FOR RECEPTOR SUGAR CHAIN
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, (2009/07/25)
A method is provided in which the recognition specificity of a virus for a receptor sugar chain can be easily determined with a simple instrument or apparatus. This method for determining the recognition specificity of a virus for a receptor sugar chain or for determining the change in a host infected in accordance with the mutation of virus includes the steps of bringing a sample of the virus into contact with a support having a polymer with sialo-oligosaccharide immobilized on the surface thereof; and assaying the degree of binding therein to determine the recognition specificity of the virus for the receptor sugar chain and to determine the change in a host range. The method is suitable for the surveillance of a virus.
