CYTORHODIN S DERIVATIVES, A PROCESS FOR THEIR PREPARATION AND THEIR USE AS MEDICAMENTS

Cytorhodin S derivatives, especially cytorhodin S-immunoglobulin complexes are disclosed. Cytorhodin S itself possesses very high anticancer activity, but the complexes act more selectively on cancer cells and are more useful as an anticancer agent. In order to produce cytorhodin S-immunoglobulin complexes, the oxo group on saccharide chain of cytorhodin S is reduced with an alkali metal cyanoborohydride in the presence of an ammonium salt or a compound having amino group to be converted to amino group or substituted amino group. Then, thus produced cytorhodin S derivatives are bound to immunoglobulin by means of a bifunctional cross-linking agent, a condensing agent or a spacer. New intermediate derivatives are also useful as an anticancer agent.