Synthesis of anthraquinonyl glucosaminosides and studies on the influence of aglycone hydroxyl substitution on superoxide generation, DNA binding, and antimicrobial properties

A series of anthraquinonyl glucosaminosides (10a-e) were synthesized by Koenigs-Knorr glycosidation of the corresponding aglycones (11a-e) with bromo sugar 12 followed by saponification. These glycosides were intended to serve as models to study the role played by the hydroxyl substituents on the aglycone portion of the antitumor anthracycline antibiotics. Superoxide generation as measured in rat heart sarcosomes was found to increase with the addition of successive hydroxyl groups to the anthraquinone nucleus. The 1,8-dihydroxy pattern was determined to generate significantly less superoxide than the 1,4-dihydroxy pattern. Hydroxyl substitution was also observed to stabilize the complex formed between the anthraquinones and DNA and was required for antibacterial activity against a number of Gram-positive organisms.