Solid-phase oligosaccharide synthesis acceptor-bound

A solid-phase oligosaccharide synthesis based on the MOP donor/acceptor methodology was developed by Hanessian and co-workers [224]. Thus, an 0-unprotected polymer-phase bound MOP donor is coupled with an excess of a partially esterified MOP acceptor. Selective removal of the ester (or related protecting groups) from the new saccharides generates a new 0-unpro-tected MOP donor to engage in a subsequent iteration. 

SCHEME 54. Major concepts for the polymer-supported/solid-phase oligosaccharide synthesis glycosyl acceptor bound approach (A) and glycosyl donor bound approach (B). 

The preceding sections discussed the strengths and weaknesses of the donor- and acceptor-bound synthetic strategies developed to date for the synthesis of complex oligosaccharides. Boons et al. recently described an approach that combines both strategies in a bidirectional solid phase oligosaccharide synthesis [67]. 

Our approach to oligosaccharide synthesis relied on the acceptor-bound solid-phase method. This method formally reduces the synthesis of carbohydrates to a repetitive cycle of glycosylation and deprotection events. It was reasoned that the repetitive nature of an acceptor-bound glycosylation method rendered it ideal for automation. Therefore, we set out to investigate the potential variables in such a scheme. 

We have developed an automated solid-phase approach for the chemical synthesis of oligosaccharides. Using an acceptor-bound solid-phase... 

---