Schmidt’s trichloroacetimidate glycosidation

Scheme 8.2 Control of anomeric selectivity in glycosidations via Schmidt s trichloroacetimidate method.

Urban, F J, Moore, B S, Breitenbach, R, Synthesis of tigogenyl 3-0-cellobioside heptaacetate and glycoside tetraacetate via Schmidt s trichloroacetimidate method some new observations. Tetrahedron Lett., 31, 4421-4424, 1990. 

Both assembly of the methyl glycoside 66 (see Scheme 29) and coupling of the appropriately protected trichloroacetimidate derivative 96 with the calicheami-cinone y precursor97 [222] (Scheme 37) using Schmidt s protocol [170c] were... 

By similar strategies, Schmidt and coworkers have also prepared a partial structure of the GPI anchor of T. gondii (O Scheme 12) [89]. First, the trichloroacetimidate 138 of a tetrasaccharide as the glycosyl donor was prepared and utilized to glycosidate pseudodisaccharide 114. The resultant hexasaccharide 139 was then selectively deprotected and phosphorylated at Man III and inositol respectively to yield 141. Quantitative deacylation followed by debenzylation over Pearlman s catalyst gave the deprotected GPI anchor 142 in a 92% yield. 

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