Iterative one-pot syntheses of chitotetroses.

Rapid syntheses of chitotetrose derivatives were achieved in good yields using the newly developed reactivity independent iterative one-pot strategy. The protective groups on donors and acceptors were independently evaluated allowing matching of the two partners in glycosylation. No anomeric reactivity adjustments or intermediate purification were necessary thus significantly improving the overall synthetic efficiency. Only near stoichiometric amounts of building blocks were required for the assembly of target molecules further highlighting the potential of the iterative one-pot method in complex oligosaccharide synthesis.