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Scope and limitations of 2-deoxy- and 2,6-dideoxyglycosyl bromides as donors for the synthesis of β-2-deoxy- and β-2,6-dideoxyglycosides.

ABSTRACT: It is shown that 2-deoxy- and 2,6-dideoxyglycosyl bromides can be prepared in high yield (72-94%) and engaged in glycosylation reactions with β:α selectivities ≥6:1. Yields of product are 44-90%. Fully armed 2-deoxyglycoside donors are viable, while 2,6-dideoxyglycosides require one electron-withdrawing substituent for high efficiency and β-selectivity. Equatorial C-3 ester protecting groups decrease β-selectivity, and donors bearing an axial C-3 substituent are not suitable. The method is compatible with azide-containing donors and acid-sensitive functional groups.

SUBMITTER: Kaneko M

PROVIDER: S-EPMC4033630 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Synthesis of highly functionalized 2,2'-bipyridines by cyclocondensation of β-ketoenamides - scope and limitations.

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