Simple methods of modification of daunorubicin on the daunosamine nitrogen atom

Modification of daunorubicin on its NH2 moiety is a well-established synthetic approach to obtain novel derivatives of this compound. Moreover, the daunosamine moiety of this antibiotic is considered to be the most sensitive part of a molecule in terms of biological response to chemical transformations. Using simple and effective synthetic techniques, namely, alkylation under phase-transfer catalysis and an amine addition across an activated multiple bond, a series of daunorubicin derivatives retaining the amine functionality have been obtained, which could also be used as potential precursors for further transformations.