%0 Journal Article %T Stereodynamic Investigation of Labile Stereogenic Centres in Dihydroartemisinin %A Ilaria D¡¯Acquarica %A Francesco Gasparrini %A Dorina Kotoni %A Marco Pierini %A Claudio Villani %A Walter Cabri %A Michela Di Mattia %A Fabrizio Giorgi %J Molecules %D 2010 %I MDPI AG %R 10.3390/molecules15031309 %X Since its identification in the early 1970s, artemisinin, as well as semi-synthetic derivatives and synthetic trioxanes, have been used in malaria therapy. Reduction of artemisinin by NaBH4 produced dihydroartemisinin (DHA), and yielded a new stereochemically labile centre at C-10, which, in turn, provided two interconverting lactol hemiacetal epimers (namely a and b), whose rate of interconversion depends on buffer, pH, and solvent polarity. Since interconversion of the two epimers occurred on a chromatographic time-scale, this prompted a thorough investigation of the phenomenon as a crucial requisite of any analytical method aimed at quantitating this family of drugs. In this critical review we discuss the current importance of the on-column epimerization of DHA in the development of analytical methods aimed at quantifying the drug, with the purpose of identifying the optimal conditions to minimize on-column epimerization while achieving the best selectivity and efficiency of the overall separation. %K Dihydroartemisinin (DHA) %K on-column epimerization %K cryo-HPLC %K dynamic HPLC (DHPLC) %K computer simulation %U http://www.mdpi.com/1420-3049/15/3/1309