An active compound has shown promising anti-malarial activity in mice infected with Plasmodium yoelii, used as a model of human malaria. Known as bis-trioxane 12a, the compound could be a potential drug candidate for malaria chemotherapy.

In recent years, artemisinin and its derivatives produced from the Chinese herb Artemisia annua have helped overcome multi-drug resistant malaria. The key to artemisinin's success is the presence of the organic compound 1,2,4-trioxanes. Given the poor bioavailability of artemisinin and its derivatives, the researchers sought ways to synthetically produce 1,2,4-trioxanes.

Resorting to a slightly modified photo-oxygenation method, the researchers prepared bis-and tris-1,2,4-trioxanes. They assessed the anti-malarial activity of 24 bis-trioxanes and 3 tris-trioxanes in mice infected with multi-drug resistant P. yoelii.

The researchers found that bis-trioxane 12a is the most active compound of the all compounds tested. It was slightly more active than arteether, a derivative of artemisinin.

"To the best of our knowledge, this is the first report on antimalarial bis- and tris-trioxanes," says lead researcher Chandan Singh from the division of medicinal and process chemistry and division of parasitology of Central Drug Research Institute, Lucknow.