Concise Synthesis of a Pentasaccharide Repeating Unit Corresponding to the O‐Antigen of Salmonella Enterica O51

Abstract

A pentasaccharide repeating unit corresponding to the cell wall O‐antigen of Salmonella enterica O51 has been synthesized as its 2‐aminoethyl glycoside adopting a sequential stereoselective glycosylation strategy. Judiciously functionalized monosaccharide intermediates were prepared and stereoselectively assembled to get the desired pentasaccharide derivative in excellent yield. An elegant one‐pot reaction condition has been applied for the stereoselective glycosylation and p‐methoxybenzyl group deprotection.

Recent progress in chemical synthesis of bacterial surface glycans

“…Synthetic targets chemically obtained include repeating units (RUs) and related oligomers or analogs of CPSs (1-25) [10,12,[19][20][21][22][23][24][25][26][46][47][48][49][50][51][52][53][54][55][56][57][58][59], LPSs and LOSs [28][29][30][31][32][33][34][35][36][37][60][61][62][63][64][65][66][67][68][69][70][71][72], cell wall polysaccharides (50)(51)(52)(53)…”

“…The LPS and LOS oligosaccharides and analogs obtained (Figure 2B) include those from B. pertussis (26) [60] ** ; P. aeruginosa STO11 (27) [61] ** ; P. shigelloide ST51 (28) [62]; B. cenocepacia (29) [28]; P. fluorescens BIM B-582 (30) [63]; H. pylori STO2 (31) [29] ** ; K. pneumoniae O2a (32) [30] ** ; P. chloroaphis UCM B-106 (33) [64]; S. boydii type type 18 (34) [65]; S. enteritidis (35) [31]; S. paratyphi A (36) [32] ** ; S. enterica O41 (37) [33], O51 (38) [66], O60 (39) [67]; E. coli O43 (40) [68], O75 (41) [69], O115 (42) [34], O156 (43) [70]; A. doebereinerae type strain GSF71 T (44) [71], P. alcalifaciens O22 (45) [78], rhizobial and agrobacterial LPS inner core (46) [72]; and C. jejuni LOS core (47) [35] ** ; Bradyrhizobium sp. BTAi1 (48) [36] ** and P. cryohalolentis K5 T (49) [37].…”