THE NATURE OF PYRACONITINE

Abstract

A new investigation of pyraconitine and pyraconie has confirmed the presence of a skeletal carbonyl in these compounds. Reduction of pyraconitine with sodium borohydride produces a hydrolytic base which no longer contains a carbonyl group. The Wolff–Kishner reaction reduces the carbonyl in pyraconitine, eliminates the elements of methanol, and hydrogenates the resulting double bond as well as hydrolyzing off the benzoyl ester. These observations indicate the presence in aconitine of the sequence R2C(OAc)• CHOH• CH(OCH3)-. On the basis of the structure of aconine previously derived from the X-ray structure of demethanolaconinone the foregoing results determine the skeletal position occupied by the labile acetoxy group in aconitine.