<jats:title>Abstract</jats:title><jats:p>From the leaves of <jats:italic>Pleiocarpa tubicina</jats:italic> S<jats:sc>TAPF</jats:sc> (+)‐Quebrachamine ((+)‐I), (−)‐1,2‐Dehydroaspidospermidine (( −)‐II), and (−)‐Aspidofractinine (IV), have been isolated in small quantities. The interesting conversion of (−)‐Quebrachamine ((−)‐I) into(+)‐1,2‐Dehydroaspidospemidine ((+)‐II) has been achieved by controlled per‐manganate oxidation.