Molecular design, chemical synthesis and biological evaluation of quinoxaline–carbohydrate hybrids as novel and selective photo-induced DNA cleaving and cytotoxic agents

The quinoxaline moiety in antitumor quinoxaline antibiotics cleaved double stranded DNA at the 5′ side guanine of the 5′-GG-3′ site upon irradiation with UV light with a long wavelength and without any additive. The quinoxaline–carbohydrate hybrid system was very effective for the DNA cleavage. Furthermore, the quinoxaline–carbohydrate hybrids exhibited strong and selective cytotoxicity against cancer cells with photoirradiation.