Englerin A possesses high toxicity for kidney cancer cells, researchers discover

Englerin A, a natural product recently discovered in an African plant, possesses high toxicity for kidney cancer cells but low toxicity for other cells. Therefore this compound is potentially qualified for further evaluation toward an application in cancer therapy. "We have noticed that one ingredient of catmint has a structure similar to that of englerin A", explains Mathias Christmann, professor of organic chemistry at TU Dortmund. As a result, he and his colleagues Dr. Matthieu Willot and graduate student Lea Radtke initiated a program to convert nepetalactone, the active substance of catmint (Nepeta cataria), into englerin A. For that reason, the molecular structure of the starting material (nepetalactone) is altered in the laboratory step-by-step, eventually culminating in the target molecule (englerin A). The first successful total synthesis, meaning the synthetic production of englerin A on the basis of catmint oil, was completed in summer 2009. The international specialized press celebrated this achievement as a "scientific highlight".

In contrast to the isolation of natural products from plants, fungi or bacteria, its chemical synthesis offers several advantages. On the one hand, synthesis sometimes is the only chance to gain access to reasonable amounts of material needed for further biological testing. On the other hand, synthesizing biologically active compounds from scratch enables chemists to focus directly on the desired effect on human cells. Whereas the possibilities to change the structure of the isolated natural product itself are often limited. If and how englerin A can be used in treatment of kidney cancer are questions, Prof. Christmann and his team want to deal with in collaboration with biologists and other scientists. But even now the team is very happy about their discovery of a synthetic route that allows the production of an active substance against kidney cancer and they conclude, "It is its own reward for a scientist to contribute something useful to a project that bears the potential to help other people."