Herein we report the first total syntheses of the trisaccharide-repeating units of Pseudomonas chlororaphis subsp. aureofaciens UCM B-306 via a one-pot assembly of the core trisaccharide structure. The rare-sugar-containing trisaccharide-repeating units are comprised of d-bacillosamine, 2-amino-2-deoxy-d-galacturonic acid or amide, and d-rhamnose units linked through three consecutive α-linkages. The total syntheses of two repeating units were completed starting from d-mannose via a longest-linear sequence of 27 steps in 5.8% and 4.4% overall yields, respectively.

Herein, we report the total synthesis of the phosphorylated zwitterionic trisaccharide repeating unit of Photorhabdus temperata subsp. cinerea 3240. The efficient route involves regio- and stereoselective assembly of trisaccharide with rare deoxyamino sugar AAT at the nonreducing end, late stage oxidation, and installation of a phosphate linker on the trisaccharide. The total synthesis was completed via a longest linear sequence of 24 steps in 6.5% overall yield.