Synthesis of 6,7-Dehydroartemisinic Acid.

The natural product 6,7-dehydroartemisinic acid from Artemisia annua has been synthesized in four steps from artemisitene, which was in turn prepared in four steps from commercially available artemisinin. The forward synthesis involves the acid degradation of artemisitene and some comparisons are made between the products from this reaction and the more extensively studied acid degradation reaction of its 11,13-dihydro analogue, artemisinin.