Sialic acid derivatives

摘要

An amine or hydrazide derivative of a sialic acid unit, e.g. in a polysaccharide, is reacted with a bifunctional reagent at least one of the functionalities of which is an ester of N-hydroxy succinimide, to form an amide or hydrazide product. The product has a useful functionality, which allows it to be conjugated, for instance to proteins, drugs, drug delivery systems or the like. The process is of particular utility for derivatising amine groups introduced in sialic acid terminal groups of polysialic acids.

主权项

1. A compound of formula III or formula VIIIwherein
(a) X is selected from a group consisting of a functional group of a NHS-ester, vinyl sulfone, N-maleimido, N-iodoacetamido, orthopyridyl disulfide, hydroxy, protected hydroxyl, amino, protected amino, carboxyl, protected carboxyl, azide and azido;
R1 is a linker;R3 is a monosaccharide, a disaccharide, an oligosaccharide, or a polysaccharide; andR4 is hydrogen or C1-4 alkyl; or (b) R1 is a linker; X is a functional group; and —R1—X is R3 is a monosaccharide, a disaccharide, an oligosaccharide, a polysaccharide; andR4 is hydrogen or C1-4 alkyl.