Structure of Azadirachtin B

Abstract

Abstract The structures of azadirachtin B and of detigloylazadirachtin have been determined on the basis of detailed 1H and 13C NMR spectroscopic analysis. Comparison of the data from both com pounds unequivocally proves esterification by tiglic acid at position 3. Our data thus confirm the structure as proposed by Klenk et al., J. Chem. Soc., Chem. Commun. 1986, 523-524.