Camptothecin

Camptothecin (molecular formula C20H16N2O4) is a cytotoxic, naturally occurring alkaloid consisting of a quinoline and an isoquinoline ring system. Camptothecin belongs structurally to the quinoline alkaloids. Camptothecin inhibits the enzyme topoisomerase I which makes this alkaloid biologically interesting. Camptothecin is extracted from the bark and roots, seeds, wood and the (young) leaves of Camptotheca acuminata, the Chinese tree of happiness. This tree, which is native to China, belongs to the tupelo family (Nyssaceae).

Camptothecin showed a cytostatic effect in clinical studies. However, the substance was not used clinically due to unfavourable physicochemical and pharmacological properties (Legarza K et al. 2005). Further developments of camptothecin are the pharmaceuticals topotecan and irinotecan. These are approved as inhibitors of the topoisomerase I inhibitors for the treatment of malignant tumors.