Glutarimide Antibiotics. XII. A Stereochemical Investigation of the Dehydration Products of Cycloheximide

The dehydration of cycloheximide using any of the previously published methods is shown to be accompanied by isomerization. The products, the anhydrocycloheximides (II and XI), belong to the isocycloheximide series in that they have m-related methyl groups. Reduction of either of these anhydrocycloheximides leads to the same saturated ketone except that in the latter case the product is racemic. A rationale for this result is presented. The alcohols derived from these ketones have been characterized and have been shown to regenerate the parent ketone on oxidation. A number of the conflicting literature reports surrounding these compounds have been reconciled.