The present invention relates to pharmaceutically active oligosaccharide conjugates having the formula: (X--Y.sub.m).sub.n--S, wherein component X is a pharmaceutically active compound, Y is a bifunctional linker, and S is an oligosaccharide consisting of 1 to 20 saccharide units, n is equal or less than the number of the saccharide units in the oligosaccharide S, and m is, independent of n, 0 or 1. In addition, the present invention is directed to a process of preparing compounds of the present invention, comprising the step of coupling compounents X and S directly or indirectly by means of a bifunctional linnker group. Furthermore, the present invention relates ot the use of said pharmaceutically active oligosaccharide conjugates as a medicament as well as to pharmaceutical compositions, freeze-dried pharmaceutical compositions, and a kit, all of which comprise at least one of said pharmaceutically active oligosaccharide conjugates.