The title compound, C(32)H(50)O(10), prepared from a mixture of α- and β-dihydro-artemisinin, has two β-arteether moieties linked via an -OCH(2)CH(2)O- bridge, so that the mol-ecule is symmetric about the bridge. Each asymmetric unit contains a β-arteether moiety and an -OCH(2) group, which is only one-half of the mol-ecule. The endo-peroxide bridges of the parent compounds have been retained in each half of the diol-bridged dimer. The rings exhibit chair and twist-boat conformations.