Application of Tris (dipivaloylmethanato) europium (III) to the Assignments of Methyl Resonances of Triterpene Acetates related to β-Amyrin

Abstract

The nuclear magnetic resonance spectra of triterpene acetates related to β-amyrin were examined by use of the shift reagent Eu (DPM)₃ and assignments of their methyl resonances have been performed. Furthermore, the most favourable conformation of the co-ordinate complex was suggested based on the consideration of molecular models and the angle term in McConnel-Robertson equation.