Structural study on adriamycin-oxidized dextran conjugate.

An adriamycin (ADM)-oxidized dextran conjugate, which may act as a potential anticancer drug with reduced side effects, was synthesized by binding of adriamycin as Schiff's base with periodate-modified dextran, preparated by partial periodate oxidation, glycylation followed second periodate oxidation. This paper has been concerned with structure of starting dextran, having one (1→43)-linked branch point per 21 α(1→6)-linked glucose resides, its periodate-modified, and glycylated derivative, and that of the final product, Adriamycin-oxidized dextran conjugate (ADM-OXD). The structure of ADM-OXD and that of intermediates at each reactive step, were elucidated mainly by methylation, periodate oxidation, Smith degradation, and also NMR. Thus, ADM-OXD was shown to consist of 1 mole of branching glucose residue, 1 mole of morpholine derivative, 4 moles of periodate-oxidized glucose residues (aldehyde groups), 12 moles of glycylating residues at C-4 and/or C-2 positions of periodate-oxidized glucose residues, and 3 moles of adriamycin conjugating oxidized-glucose residues, respectively, per repeating units(21 glucose residues) of dextran T-70.