Cancer will be the major cause of death in the 21st century and natural products should provide novel and more effective anticancer agents. This review deals with new natural molecules liable to become anticancer drugs, as well as recent specific strategies for a selective treatment of cancer. The introduction presents the current state of the art on anticancer research. Beside, in the following subheadings we summarize our research on cytotoxic natural quinone methide-triperpenes and their analogues. We also discuss our results on the anti-tumour promoting activity of natural naphthoquinones and their derivatives.

A new series of coumarin-1,2,3-triazole conjugates with varied alkyl, phenyl and heterocycle moieties at C-4 of the triazole nucleus were synthesized using a copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction of corresponding O-propargylated coumarin (3) or N-propargylated coumarin (6) with alkyl or aryl azides. Based on their minimal inhibitory concentrations (MICs) against selected microorganisms, six out of twenty-six compounds showed significant antibacterial activity towards Enterococcus faecalis (MIC = 12.5–50 µg/mL). Moreover, the synthesized triazoles show relatively low toxicity against human erythrocytes.