Mass spectrometry in cardenolide chemistry—II

Six partial acetates of gitoxin have been used to establish the value of mass spectrometry, when used in conjunction with deuteroacetylation, in cardenolide structural studies. This technique permits the unambiguous location of acetyl groups upon any of the digitoxose residues, and in some cases confirms acetylation of C16 of the steroid ring. The method is suitable for metabolic studies. The spectra discussed show that neither acetyl exchange nor acetyl migration reactions had taken place during the deuteroacetylation step.