DNA Topoisomerase I inhibitors

Natural Product-Inspired Drugs. Camptothecin, an alkaloid isolated from Camptotheca acuminata, is a potent inhibitor of DNA topoisomerase I. Numerous useful analogs of camptothecin have been synthesized: SN-38 and Topotecan exhibit improved water solubility, while Irinotecan is a prodrug. For a review of camptothecin analogs as cancer therapeutics, see Amin et al. Anticancer Agents Med Chem.