An efficient total synthesis of(−)-C10-desmethyl arteannuin B (5) has beenachieved. The sequencefeatures the use of a chiral auxiliary to introduce absolute asymmetryat an early stage and astereoselective, chelation-controlled reductive cyclization of8, using samarium diiodide as thereducing agent. The methodology promises to be applicable to thesynthesis of a wide range ofanalogs capable of being converted to potent antimalarial agentsrelated to artemisinin (1).