29847-23-2Relevant articles and documents
A (13)C-N.M.R. INVESTIGATION OF GLYCOSYL AZIDES AND OTHER AZIDO SUGARS: STEREOCHEMICAL INFLUENCES ON THE ONE-BOND (13)C-(1)H COUPLING CONSTANTS
Szilagyi, Laszlo,Gyoergydeak, Zoltan
, p. 21 - 42 (1985)
Unambigous (13)C assignments have been obtained, using 2D-n.m.r. techniques, for several glycosyl azides, 6-deoxyglucosyl azides, 2-acylamino-2-deoxyglycosyl azide, and some 2- and 3-azido monosaccharide derivatives.For non-anomeric C-H-bonds the 1JC,Heq. values are 4-9 Hz larger than the 1JC,Hαx. values.A substituent (hydroxyl, acetoxyl, alkoxyl, azido, etc.) in 1,3-diaxial relationship with Hax. significantly increases the value of 1JC,Hαx..Bond-angle distortions in the fused-ring bicyclic systems of some isopropylidene derivatives result in 1JC,Hαx. values being larger than 1JC,Heq. values.Electronic and stericeffects of substituents at non-anomeric carbons may alter the 1JC,H values for anomeric carbons to such an extent that they may no longer be useful for diagnosing anomeric configuration.Bond-angle deformations also influence the (13)C chemical shift differences in α- and β-anomers at C-5 and, to a lesser extent, at C-3.
Synthesis of Asparagine Derivatives Harboring a Lewis X Type DC-SIGN Ligand and Evaluation of their Impact on Immunomodulation in Multiple Sclerosis
Doelman, Ward,Marqvorsen, Mikkel H. S.,Chiodo, Fabrizio,Bruijns, Sven C. M.,van der Marel, Gijsbert A.,van Kooyk, Yvette,van Kasteren, Sander I.,Araman, Can
, p. 2742 - 2752 (2020/12/29)
The protein myelin oligodendrocyte glycoprotein (MOG) is a key component of myelin and an autoantigen in the disease multiple sclerosis (MS). Post-translational N-glycosylation of Asn31 of MOG seems to play a key role in modulating the immune response towards myelin. This is mediated by the interaction of Lewis-type glycan structures in the N-glycan of MOG with the DC-SIGN receptor on dendritic cells (DCs). Here, we report the synthesis of an unnatural Lewis X (LeX)-containing Fmoc-SPPS-compatible asparagine building block (SPPS=solid-phase peptide synthesis), as well as asparagine building blocks containing two LeX-derived oligosaccharides: LacNAc and Fucα1-3GlcNAc. These building blocks were used for the glycosylation of the immunodominant portion of MOG (MOG31-55) and analyzed with respect to their ability to bind to DC-SIGN in different biological setups, as well as their ability to inhibit the citrullination-induced aggregation of MOG31-55. Finally, a cytokine secretion assay was carried out on human monocyte-derived DCs, which showed the ability of the neoglycopeptide decorated with a single LeX to alter the balance of pro- and anti-inflammatory cytokines, inducing a tolerogenic response.
Radical-Mediated Acyl Thiol-Ene Reaction for Rapid Synthesis of Biomolecular Thioester Derivatives
Lynch, Dylan M.,McLean, Joshua T.,McSweeney, Lauren,Milbeo, Pierre,Scanlan, Eoin M.
, p. 4148 - 4160 (2021/08/24)
The thiol-ene ‘click’ reaction has emerged as a versatile process for carbon–sulfur bond formation with widespread applications in chemical biology, medicinal chemistry and materials science. Thioesters are key intermediates in a wide range of synthetic and biological processes and efficient methods for their synthesis are of considerable interest. Herein, we report the first examples of acyl-thiol-ene (ATE) for the synthesis of biomolecular thioesters, including peptide, lipid and carbohydrate derivatives. A key finding is the profound effect of the amino acid side chain on the outcome of the ATE reaction. Furthermore, radical generated thioesters underwent efficient S-to-N acyl transfer and desulfurisation to furnish ‘sulfur-free’ ligation products in an overall amidation process with diverse applications for chemical ligation and bioconjugation.
A Tripeptide Approach to the Solid-Phase Synthesis of Peptide Thioacids and N-Glycopeptides
Sch?we, Markus Julian,Keiper, Odin,Unverzagt, Carlo,Wittmann, Valentin
supporting information, p. 15759 - 15764 (2019/11/19)
A general and robust method for the incorporation of aspartates with a thioacid side chain into peptides has been developed. Pseudoproline tripeptides served as building blocks for the efficient fluorenylmethyloxycarbonyl (Fmoc) solid-phase synthesis of t
