Heterocyclic compounds are of particular interest in medicinal science. This has accelerated the quest for new methods in heterocyclic chemistry. A particular class of alkaloids that incorporate the pyrroloquinazoline chromophore have been isolated from natural sources [1] and display a wide range of biological activities.[2] Among them, luotonin A is a human DNA topoisomerase I poison, which has been isolated from Peganum nigellastrum, a Chinese ...