Synthesis of polyribosylribitol phosphate oligosaccharides

摘要

Polyribosylribitol phosphate oligosaccharides are produced in a multistep process. The compound of the formula: wherein R1 is a first protecting group and R2 is a second protecting group, is coupled to a solid polyethylene glycol monomethyl ether (PEG) support. Following removal of the first protecting group, the resulting compound is coupled with a repeating unit for chain elongation of the formula: The protecting group is removed from the phosphorus atom and the steps of removing the first protecting group, coupling with the repeating unit is repeated until the desired number of repeating units in the oligomer has been terminated. The oligomer then is terminated with a chain terminating molecule of the formula: wherein m is an integer and R3 is a third protecting group. The resulting PEG-bound protected oligomer is a new product and the oligomer may be cleaved from the support and processed to provide a chemically-reactive functional group for binding the polysaccharide oligomer to a carrier molecule.