316188-11-1Relevant articles and documents
Prearranged glycosides. Part 12. Intramolecular mannosylations of glucose derivatives via prearranged glycosides
Lemanski, Gregor,Ziegler, Thomas
, p. 2655 - 2675 (2000)
A series of prearranged glycosides 5, 17, 23, 28, 37, and 41, having a benzyl-protected 1-thiomannosyl donor linked through its positions 2, 3, 4, and 6 via succinate and malonate tethers, respectively, to positions 2, 3, and 6 of a benzyl glucopyranoside acceptor, were prepared by condensation of the respective mannosyl succinates and malonates with suitably protected benzyl glucopyranosides. The prearranged glycosides were intramolecularly coupled under various conditions to give the corresponding tethered (1 → 4)-linked disaccharides. The yields and anomer ratios of the products of these couplings were interpreted in terms of the thermodynamic stability of the resulting disaccharides. In the case of prearranged glycoside 17, having positions 3 of both the donor and the acceptor linked by a succinate tether, a strong dependence of the diastereoselectivity of the intramolecular glycosylation on the activation procedure was observed. All other cases did not show a significant dependence of the outcome of the anomeric configuration in intramolecular glycosylation on the activation procedure or the solvent.
Studies on the substrate specificity of a GDP-mannose pyrophosphorylase from Salmonella enterica
Zou, Lu,Zheng, Ruixiang Blake,Lowary, Todd L.
supporting information; experimental part, p. 1219 - 1226 (2012/09/21)
A series of methoxy and deoxy derivatives of mannopyranose-1-phosphate (Manp-1P) were chemically synthesized, and their ability to be converted into the corresponding guanosine diphosphate mannopyranose (GDP-Manp) analogues by a pyrophosphorylase (GDP-ManPP) from Salmonella enterica was studied. Evaluation of methoxy analogues demonstrated that GDP-ManPP is intolerant of bulky substituents at the C-2, C-3, and C-4 positions, in turn suggesting that these positions are buried inside the enzyme active site. Additionally, both the 6-methoxy and 6-deoxy Manp-1P derivatives are good or moderate substrates for GDP-ManPP, thus indicating that the C-6 hydroxy group of the Manp-1P substrate is not required for binding to the enzyme. When taken into consideration with other previously published work, it appears that this enzyme has potential utility for the chemoenzymatic synthesis of GDP-Manp analogues, which are useful probes for studying enzymes that employ this sugar nucleotide as a substrate.
Dispiroketals in synthesis (part 5): A new opportunity for oligosaccharide synthesis using differentially activated glycosyl donors and acceptors
Boons, Geert-Jan,Grice, Peter,Leslie, Ray,Ley, Steven V.,Yeung, Lam Lung
, p. 8523 - 8526 (2007/10/02)
The reactivity of dispiroketal protected thioglycosides makes them useful new precursors for oligosaccharide synthesis as is illustrated by the preparation of a protected pentasaccharide unit common to the variant surface glycoprotein of Trypanosoma bruce