Synthesis of the saccharomicin fucose-aglycon conjugate and determination of absolute configuration.

ABSTRACT

[reaction see text] Schmidt glycosylation of the appropriately protected 3,4-dihydroxycinnamate methyl ester with 2,3,4-triacetoxyfucopyranosyltrichloroacetimidate gives aryl glycoside in high yield and diastereoselectivity. 2-Sulfation of fucose, installation of taurine, and global deprotection of the remaining protecting groups affords the fucose-aglycon conjugate of saccharomicin. This synthesis which arises from L-fucose also establishes the absolute configuration of the reducing terminus of the saccharomicin oligosaccharide.