Synthesis and antifungal activity of pradimicin derivatives. Modifications of the sugar part.

Modifications at the sugar part of pradimicins were carried out by glycosidations of the aglycones or chemical transformations of natural pradimicins and their antifungal activity was evaluated. Among them, some of the D-xylose-modified derivatives (14, 17, 24) showed activity comparable to that of pradimicin A. The structure-activity relationships obtained through there studies clarified the role of the sugar part in the manifestation of antifungal activity: The 5-O-(6-deoxy-beta-D-sugar) is essential for activity and 2'-epi, 3'-oxo and 4'-deoxy sugar derivatives retain activity against yeasts.