Synthesis and biochemical properties of E-ring modified luotonin A derivatives

Luotonin A is a cytotoxic pyrroloquinazolinoquinoline alkaloid that has been shown to stabilize the human topoisomerase I–DNA covalent binary complex in the same fashion as the antitumor alkaloid camptothecin. A study of the structural elements in luotonin A required for binary complex stabilization has revealed key differences relative to those required for camptothecin.