Gas chromatographic analysis of norcantharidin and related compounds using derivatization to imides

Derivatization to imides has been studied for determining alpha,beta-diacids or corresponding anhydrides (e.g. norcantharidin) as well as for analysing primary amines by gas chromatography. 2-Naphthylaniline, n-heptylamine, cyclohexamine, 2,5-dimethoxyaniline, 2,4,5-trichloroaniline, 3,5-dichloroaniline, aniline and benzylaniline were used as derivatization reagents. 1H-nuclear magnetic resonance and mass spectrometry data were obtained for the norcantharidin N-imides synthesized. Factors such as derivatization yields, linearity, reproducibility and sensitivity were evaluated. The influences of reaction temperature and solvent were investigated.