Stereoselective α‐Glycosylation with GlcN3 Donors Enabled Collective Syntheses of Acinetobacter baumannii Capsular Polysaccharides K43, K47 and K88 Repeating Units†

Comprehensive Summary Collective syntheses of A. baumannii CPS K43, K47 and K88 repeating units have been accomplished via a new α‐glycosylation method with GlcN 3 as donors, which features: 1) mild reaction conditions, 2) good to high yields, 3) excellent stereoselectivities. The synthetic route also highlights an orthogonal one‐pot coupling strategy on the basis of glycosyl ortho ‐(1‐phenylvinyl)benzoates for stereoselective constructions of both 1,2‐ trans and 1,2‐ cis glycosidic bonds, precluding the issues of aglycone transfer.