Structure of 11-epi-deoxyarteether formed from deoxyarteether and its alfa-isomer by treatment with acid in ethanol was established. It could be shown that this reaction proceeds via an intermediate vinylic ether. Treatment of deoxydihydroquinghaosu with toluene sulfonic acid in benzene afforded a dimer which was elucidated in its structure by an X-ray analysis. These compounds were made in connection with the WHO-program on arteether, an antimalarial prepared from the Chinese drug quinghaosu (artemisinin).
