22566-82-1Relevant articles and documents
Versatile functionalization of polylysine: Synthesis, characterization, and use of neoglycoconjugates
Thoma, Gebhard,Patton, John T.,Magnani, John L.,Ernst, Beat,?hrlein, Reinhold,Duthaler, Rudolf O.
, p. 5919 - 5929 (1999)
Glycopolymers are useful macromolecules with a non-carbohydrate backbone for presenting saccharides in a multivalent form. Here, a new methodology is described which allows easy access to water-soluble, biodegradable glycopolymers with both predeterminable composition and molecular weight distribution. Thus, chloroacetylation of commercially available polylysine hydrobromide 3 gave the reactive homopolymer 4, whose chloroacetamide functions allowed subsequent coupling with thiol-containing components. Water-soluble homopolymers such as 8 and 13 were available by treatment with an excess of hydrophilic thiols. Heteroglycopolymers were obtained via quantitave incorporation of substoichiometric amounts of carbohydrates with a mercapto functionality linked to the reducing end; the remaining chloroacetamide groups were capped with an excess of thioglycerol. A variety of glycopolymers with up to four different components was prepare. The composition and purity of the products were reliably analyzed by 1H NMR. Generally, the quantitative incorporation of substoichiometric components was verified. The polymer backbone was not altered under the applied reaction conditions, as indicated by very similar polydispersities and degrees of polymerization of starting polylysine 3 and functionalized homo- and heteropolymers 8, 13, and 14. Glycopolymer 25, containing sialyl Lewisa and biotin as a functional group for enzyme-linked immunosorbent assay, was used for developing cell-free selectin ligand binding assays. The inhibition of E- selectin by glycopolymers 16, containing sialyl Lewis(x) (sLE(x)), was evaluated in a cell adhesion assay under flow conditions using activated human umbilical vein endothelial cells and polymorphonuclear neutrophils. The sLe(x) polymers 16 showed no significant inhibition, whereas conjugates with additional charged groups (carboxylates 18, sulfonates 21) in addition to sLe(x) gave 30-35% reduction of the number of interacting cells at the same concentration of 100 μM sLe(x).
Applications of Shoda's reagent (DMC) and analogues for activation of the anomeric centre of unprotected carbohydrates
Fairbanks, Antony J.
, (2020/12/07)
2-Chloro-1,3-dimethylimidazolinium chloride (DMC, herein also referred to as Shoda's reagent) and its derivatives are useful for numerous synthetic transformations in which the anomeric centre of unprotected reducing sugars is selectively activated in aqueous solution. As such unprotected sugars can undergo anomeric substitution with a range of added nucleophiles, providing highly efficient routes to a range of glycosides and glycoconjugates without the need for traditional protecting group manipulations. This mini-review summarizes the development of DMC and some of its derivatives/analogues, and highlights recent applications for protecting group-free synthesis.
Hypervalent Iodine Reagents: Thiol Derivatization with a Tetrafluoroethoxy Coumarin Residue for UV Absorbance Recognition
Commare, Bruno,Togni, Antonio
, (2017/05/26)
A new hypervalent iodine reagent (5) based on 1,2-dihydro-3,3-dimethyl-1,2-benziodoxole containing a 4-methyl-7-tetrafluoroethoxycoumarin unit as a specific UV absorber was prepared and fully characterized, including X-ray crystal structural analysis. The high reactivity of this compound towards thiols has been exploited for the selective tagging of several targets with the UV chromophore coumarin, including e.g. glutathione.
