NMR and conformational studies of the antimalarial drug arte-ether

The H-1 and C-13 NMR spectra of the antimalarial drug arte-ether (a derivative of qinghaosu) have been obtained and stereospecific assignments made using standard one- and two-dimensional techniques. Proton homonuclear spin-coupling constants were quantified from J-resolved and E.COSY experiments and confirmed that the solution conformation of arte-ether is similar to that of the reported crystal structure of artmether. A conformational model was generated using AM1 semi-empirical energy calculations, and was consistent with both the measured spin-coupling constants and experimental NOE data.