Orthogonal glycosidations

Scheme 2.71 Principle of "orthogonal glycosidic activation on a polymer (e.g. polyethylene glycol) support, lb facilitate purification, a hydrophobic tag (e.g. 2-(trimethylsilyl)ethyl) is introduced [158]. Conditions A are for thioglycoside activation, conditions B for activation of glycosyl fluorides.

Scheme 7.4 Orthogonal glycosidation formation of selenodisaccharide 23 everninomicin 24—an application.

Scheme 7.5 Orthogonal glycosidation primary activation by a Lewis acid.

Notes and discussion. Trichloroacetimidates are versatile glycosyl donors and have played crucial roles in oligosaccharide assembly strategies [37, 38]. Takahashi et al. were the first to apply this strategy to a one-pot, two-step orthogonal glycosidation protocol [11]. 

Chapter 7 Modern Glycosidation Methods Orthogonal Glycosidation,... 

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