Design and syntheses of aryl-fused quinoxalenediynes

CHED 373

Andro C. Rios, gozamos@hotmail.com and John D. Spence, jspence@csus.edu. Department of Chemistry, California State University Sacramento, 6000 J Street, Sacramento, CA 95819
The Bergman cyclization of enediynes to produce 1,4-benzenoid diradical intermediates has been attributed to the potent ability of natural products like calicheamicin to cleave DNA. To employ enediynes as viable pro-drugs we have prepared heteroaromatic enediynes designed to improve DNA binding and photochemical activation. We have developed facile syntheses of aryl-fused quinoxalenediynes from the condensation of aromatic 1,2-diones with a diaminoarenediyne. Using this approach we have prepared nine terminal arenediynes and have studied thermal Bergman cyclization by differential scanning calorimetry. We have also prepared select phenylethynyl derivatives to pursue photochemical activation where our models absorb light between 400 nm to 600 nm.