| abstract |
The present invention relates to glycosyl-etoposide prodrugs of formula I, processes for their preparation and their use in combination with functionalized tumor-specific enzyme conjugates for the treatment of cancer, and particularly relates to 4'-O-glycosyl-etoposides as prodrugs which can be split into cytotoxic active substances under the influence of tumor-specific enzyme conjugates, the released active substance being suitable for the treatment of cancer due to its cytostatic activity. wherein R¹ is a methyl, benzyl or 2-thienyl group, R² is a hydrogen atom, an acyl or tri-C₁-C₄-alkylsilyl protective group, R³ is a hydroxyl group, an acyl or tri-C₁-C₄-alkylsilyl protective group bonded via an oxygen atom, an amino, acetylamino, benzyloxycarbonylamino or dimethylamino group, R⁴ represents a hydrogen atom or a methyl group, R⁵ is a hydrogen atom, a hydroxyl group, an acyl or tri-C₁-C₄-alkylsilyl protective group bonded via an oxygen atom, an amino, benzyloxycarbonylamino, azido or acetylamino group, R⁶ is a hydroxyl group, an acyl or tri-C₁-C₄-alkylsilyl protective group bonded via an oxygen atom, an amino, benzyloxycarbonylamino or azido group, R⁷ is a hydrogen atom, an acyl or tri-C₁-C₄-alkylsilyl protective group and R⁸ is a methyl, hydroxymethyl or an acyl protective group bonded via a methyleneoxy group or a benzyloxycarbonyl group, where an acyl protecting group is to be understood as meaning an acetyl, mono-, di- or trihaloacetyl group with halogen, fluorine or chlorine. |