Synthesis of a trisaccharide repeat of the zwitterionic Sp1 capsular polysaccharide utilizing 2-azido-4-benzylamino-4N,3-O-carbonyl-2,4,6-trideoxy-d-galactopyranosyl trichloroacetimidate

Total Synthesis of the Repeating Unit of Streptococcus pneumoniae Zwitterionic Polysaccharide Sp1

“…Subsequently, Codée and co-workers developed a conceptually different route to synthesize each of the three possible frame-shift Sp1 trisaccharide repeating units ( I , II , and III ) as glycerol conjugates by employing directly a d -galacturonic acid-[3,6]-lactone building block locked in a 1 C 4 conformation to obtain selectivity in glycosylation; AAT was synthesized from d -glucosamine . Bundle and co-workers also accomplished the synthesis of the frame-shift molecule of Sp1 trisaccharide II as a methyl glycoside using an AAT donor procured from d -glucal . Seeberger and co-workers reported a synthesis of the same frame-shift Sp1 II appended with a thiol linker; AAT was synthesized from l -threonine via a de novo synthetic route …”

“…7 Bundle and co-workers also accomplished the synthesis of the frame-shift molecule of Sp1 trisaccharide II as a methyl glycoside using an AAT donor procured from D-glucal. 8 Seeberger and co-workers reported a synthesis of the same frame-shift Sp1 II appended with a thiol linker; AAT was synthesized from L-threonine via a de novo synthetic route. 9 Our laboratory has established an efficient route for the synthesis of rare deoxyamino sugars including AAT via the regioselective one-pot displacement of D-rhamnosyl 2,4bistriflates.…”