The mixture of artemotil and alpha-arteether is used in patients with cerebral malaria. Both beta and alpha/beta arteether have comparable activity and are curative at a dose of 5 mg/kg for 3 days against blood-induced Plasmodium cynomolgi B infection in the rhesus monkey; alpha arteether alone is slightly less active, with a 50% cure rate at the above dose. Alpha-arteether is a fourth generation anti-bacterial and anti-fungal drug. Alpha-arteether was found to inhibit the growth of E-coli strains defective in DNA-gyrase enzyme. DNA gyrase mutants were sensitive to α-arteether whereas the wild type of E-coli having intact DNA gyrase genes were not sensitive to α-arteethers. In fact, the isomer of this compound, β-arteether, does not exhibit this activity. The beta-isomer of arteether was characterized by a longer elimination half-life and a relatively larger volume of distribution than the alpha-isomer, suggesting that beta-arteether may be responsible for the prolonged in vivo schizontocidal activity.