ENANTIOMERIC PURITY CONTROL OF CHIRALIC D RUGS

The enantiomeric purity control of ephedrine-HCl, norephedrine-HCl, ma ndelic acid and levamisole-HCl is investigated by means of DSC and CD. The precision of thermal analysis increases with the difference of me lting points between enantiomer and eutectic. The interpretation of me lting enthalpy is more trustworthy than the onset temperature of melti ng. The thermogravimetric noticeable decomposition of levamisole prohi bits the DSC purity control, because the onset temperature of degradat ion is below he melting temperature, The CD of ephedrine and levamisto le is in the same size, therefore the purity of these compounds is det erminable with the same precision (s(rel) +/- 3%). The CD investigatio n in solution is preferable to the thermic solid matter analysis.