Amine-catalyzed transformation of enolic nonenzymic browning products, isomaltol glycopyranosides into 1,6-anhydro-β-d-hexopyranoses

Goodwin, James C.

doi:10.1016/s0008-6215(00)90695-5

Cited by 2 publications

(1 citation statement)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A mixture of l,6-anhydro-2,3,4-tri- O -acetyl-β- d -galactopyranose 4 (83) (0.77 g, 2.67 mmol) and N -bromosuccinimide (1.9 g, 10.6 mmol)) in trifluorotoluene (40 mL) was refluxed over a 300 W heat lamp for 8 h. After 8 h, the solvent was evaporated under reduced pressure and the crude product dissolved in EtOAc (50 mL). The solution was successively washed with aqueous saturated Na 2 S 2 O 3 , aqueous saturated NaHCO 3 , and dried over Na 2 SO 4 .…”

Section: Methodsmentioning

confidence: 99%

Interplay of Protecting Groups and Side Chain Conformation in Glycopyranosides. Modulation of the Influence of Remote Substituents on Glycosylation?

2018

View full text Add to dashboard Cite

The synthesis and conformational analysis of a series of phenyl 2,3,6-tri-O-benzyl-β-d-thio galacto- and glucopyranosides and their 6S-deuterio isotopomers, with systematic variation of the protecting group at the 4-position, are described. For the galactopyranosides, replacement of a 4-O-benzyl ether by a 4-O-alkanoyl or aroyl ester results in a small but measurable shift in side chain population away from the trans,gauche conformation and in favor of the gauche,trans conformer. In the glucopyranoside series on the other hand, replacement of a 4-O-benzyl ether by a 4-O-alkanoyl or aroyl ester results in a small but measurable increase in the population of the trans,gauche conformer at the expense of the gauche,gauche conformer. The possible modulating effect of these conformational changes on the well-known changes in the anomeric reactivity of glycosyl donors as a function of protecting group is discussed, raising the possibility that larger changes may be observed at the transition state for glycosylation. A comparable study with a series of ethyl 2,3,4-tri-O-benzyl-β-d-thioglucopyranosides reveals that no significant influence in side chain population is observed on changing the O6 protecting group.

show abstract

Section: Methodsmentioning

confidence: 99%