Fragments of biopolymers containing glycosyl phosphate residues. 9. Synthesis of tetra(2-acetamido-2-deoxy-D-glucopyranosyl)triphosphate, a tetramer fragment of the capsular antigen of Escherichia coli K51
A. V. Nikolaev, I. A. Ivanova, V. N. Shibaev
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow
Abstract: Linear tetra(N-acetylglucosaminyl)tri phosphate GlcNAc(α)-P-3GlcNAc(α)-P-3GlcNAc(α)-P-3GlcNAc(β)-ONp, a fragment of the capsular antigen of E. coli K51, was synthesized by the step-by-step approach with the use of the H-phosphonate method, starting the chain from p-nitrophenyl 2-acetamido-4,6-di-O-benzoyl-2-deoxy-β-D-gluco-pyranoside. The elongation cycle included the coupling of 2-acetamido-4,6-di-O-benzoyl-2-deoxy-3-O-p-methoxybenzyl-α-D-glucopyranosyl H-phosphonate with a hydroxyl component in the presence of Me3CCOCl followed by oxidation (I2) and de(methoxybenzyla-tion) (Ce (N H4) 2 (NO3) 6). 2-Acetamido-3,4,6-tri-O-benzoyl-2-deoxy-α-D-glucopyranosyl H-phosphonate was employed in the final step. After mild debenzoylation the title tetramer was isolated by anion-exchange chromatography. The data of 1H, 13C and 31P NMR spectra of the synthesized oligomers are discussed.
Russian Journal of Bioorganic Chemistry 1992, 18 (1):126-141