Structures of decasaccharide and tridecasaccharide tetraphosphates isolated by strong alkaline degradation of O-deacylated lipopolysaccharide of Pseudomonas fluorescens strain ATCC 49271

Mild hydrazinolysis of Pseudomonas fluorescens strain ATCC 49271 lipopolysaccharide (LPS) followed by strong alkaline degradation and purification by anion-exchange HPLC resulted in two phosphorylated oligosaccharides (1 and 2). On the basis of compositional analysis and 1H, 13C, and 31P NMR spectroscopy, including 2D correlation spectroscopy (COSY), 2D rotating frame NOE spectroscopy (ROESY), and 2D inverse mode H-detected heteronuclear 1H13C and 1H31P correlation spectroscopy, the following two structures (1 and 2) could be identified where Hep is l-glycero-d-manno-heptose, Kdo is 3-deoxy-d-manno-octulosonic acid, Non is 5,7-diamino-3,5,7,9-tetradeoxy-d-glycero-l-galacto-nonulosonic acid, and P is phosphate.