34213-34-8Relevant articles and documents
Efficient Synthesis of Muramic and Glucuronic Acid Glycodendrimers as Dengue Virus Antagonists
García-Oliva, Cecilia,Cabanillas, Alfredo H.,Perona, Almudena,Hoyos, Pilar,Rumbero, ángel,Hernáiz, María J.
supporting information, p. 1588 - 1596 (2020/02/05)
Carbohydrates are involved in many important pathological processes, such as bacterial and viral infections, by means of carbohydrate-protein interactions. Glycoconjugates with multiple carbohydrates are involved in multivalent interactions, thus increasing their binding strengths to proteins. In this work, we report the efficient synthesis of novel muramic and glucuronic acid glycodendrimers as potential Dengue virus antagonists. Aromatic scaffolds functionalized with a terminal ethynyl groups were coupled to muramic and glucuronic acid azides by click chemistry through optimized synthetic strategies to afford the desired glycodendrimers with high yields. Surface Plasmon Resonance studies have demonstrated that the compounds reported bind efficiently to the Dengue virus envelope protein. Molecular modelling studies were carried out to simulate and explain the binding observed. These studies confirm that efficient chemical synthesis of glycodendrimers can be brought about easily offering a versatile strategy to find new active compounds against Dengue virus.
The stereoselectivities of tributyltin hydride-mediated reductions of 5-bromo-d-glucuronides to l-iduronides are dependent on the anomeric substituent: Syntheses and DFT calculations
Mohamed, Shifaza,Krenske, Elizabeth H.,Ferro, Vito
, p. 2950 - 2960 (2016/03/12)
One of the shortest synthetic routes to l-iduronic acid derivatives is via free radical reduction of the C-5 bromide of the corresponding protected d-glucuronic acid derivative. The epimerization of such C-5 bromides to the l-ido derivatives via reaction with tributyltin hydride was investigated. It was found that the stereoselectivity of the reaction was dependent on the anomeric substituent. If the substituent was fluoride the l-ido product was obtained exclusively in 65-72% yield whereas the O-methyl or O-acetyl derivatives led to isomeric mixtures of both the l-ido and d-gluco products in different ratios depending on the reaction conditions. DFT calculations were performed to determine the stereoelectronic factors that favour formation of the l-ido isomer from the fluoride and suggest the selectivity is due to a transition state gauche effect and an Sn-F interaction.
Glycoside cleavage by a new mechanism in unsaturated glucuronyl hydrolases
Jongkees, Seino A. K.,Withers, Stephen G.
, p. 19334 - 19337 (2012/01/31)
Unsaturated glucuronyl hydrolases (UGLs) from GH family 88 of the CAZy classification system cleave a terminal unsaturated sugar from the oligosaccharide products released by extracellular bacterial polysaccharide lyases. This pathway, which is involved in extracellular bacterial infection, has no equivalent in mammals. A novel mechanism for UGL has previously been proposed in which the enzyme catalyzes hydration of a vinyl ether group in the substrate, with subsequent rearrangements resulting in glycosidic bond cleavage. However, clear evidence for this mechanism has been lacking. In this study, analysis of the products of UGL-catalyzed reactions in water, deuterium oxide, and dilute methanol in water, in conjunction with the demonstration that UGL rapidly cleaves thioglycosides and glycosides of inverted anomeric configuration (substrates that are resistant to hydrolysis by classical glycosidases), provides strong support for this new mechanism. A hydration-initiated process is further supported by the observed UGL-catalyzed hydration of a C-glycoside substrate analogue. Finally, the observation of a small β-secondary kinetic isotope effect suggests a transition state with oxocarbenium ion character, in which the hydrogen at carbon 4 adopts an axial geometry. Taken together, these observations validate the novel vinyl ether hydration mechanism and are inconsistent with either inverting or retaining direct hydrolase mechanisms at carbon 1.
