Simple formylacetal (CH2) as a novel linker for saccharide synthesis on soluble-polymer support

Described herein is a new formylacetal (CH2) linker for immobilization of small molecules onto a soluble-polymer support, poly(ethylene glycol) ω-monomethyl ether (MPEG), and its application to saccharide synthesis. This small linker allows immobilization of a hindered hydroxy group such as the 4-hydroxy group of glucose onto MPEG. The linker is stable under several reaction conditions including glycosylation. Removal of this support was found to be achieved through cleavage of the CH2 linker either by a Lewis acid (TMSI or Ce(OTf)x) or a Brønsted acid (trifluoroacetic acid) in moderate to good yields. In combination with solid acid catalyst, simpler operations became possible during the working-up and purification processes.