Solid-phase synthesis of a branched hexasaccharide using a highly efficient synthetic strategy.

F Roussel; M Takhi; R R Schmidt

doi:10.1021/jo016018p

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PubMed · 11735536

Solid-phase synthesis of a branched hexasaccharide using a highly efficient synthetic strategy.

F Roussel·M Takhi·R R Schmidt

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Abstract

The solid-phase synthesis of branched lacto-N-neohexaose derivative 1 occurring in human milk is described. The new building block of lactose 3 bearing the orthogonal temporary hydroxy protecting groups 9-fluorenylmethyloxycarbonyl (Fmoc) and levulinoyl (Lev) has been prepared. Its use, together with that of lactosamine donor 4, glucosamine donor 5, and O-galactosyl trichloroacetimidate 6, has enabled the preparation of hexasaccharide 22 following two different approaches in excellent overall yield (43%, 90% per step over eight steps). An additional key feature of this work is the successful use of newly prepared ester-type linker 2, having a benzylic spacer connected to the anomeric oxygen. This linker presents the advantage of producing a benzylic anomeric moiety after cleavage from the polymer support, which could be easily removed to obtain the unprotected oligosaccharide 1.

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Carbohydrate Sequence Cross-Linking Reagents Esters Fluorenes Glucosamine Lactose Milk, Human Molecular Sequence Data Oligosaccharides Journal Article Research Support, Non-U.S. Gov't

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F Roussel, M Takhi, R R Schmidt. 2001-12-14. Solid-phase synthesis of a branched hexasaccharide using a highly efficient synthetic strategy.. https://doi.org/10.1021/jo016018p

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