<jats:p><jats:bold>The structure of the spermine alkaloid aphelandrine from <jats:italic>Aphelandra squarrosa</jats:italic> N<jats:sc>EES</jats:sc></jats:bold><jats:p>The new spermine alkaloid aphelandrine (<jats:bold>2</jats:bold>) has been isolated from <jats:italic>Aphelandra squarrosa</jats:italic> N<jats:sc>EES</jats:sc>. By oxidation of <jats:bold>2</jats:bold> with KMnO<jats:sub>4</jats:sub> followed by methylation (CH<jats:sub>2</jats:sub>N<jats:sub>2</jats:sub>) <jats:bold>12</jats:bold> and <jats:bold>14</jats:bold> could be prepared (<jats:italic>Scheme 2</jats:italic>). Fusion of <jats:bold>2</jats:bold> with KOH yielded spermine (<jats:bold>1</jats:bold>) whereas hydrolysis of <jats:bold>2</jats:bold> in hot hydrochloric acid results in lacton <jats:bold>17</jats:bold>, the structure of which could be elucidated by comparison with a synthetically prepared model compound (<jats:italic>Scheme 3</jats:italic>). The benzylic bonds N (10), C(11) as well as O(16), C(17) of <jats:bold>2</jats:bold> could be cleaved by hydrogenolysis (compare <jats:bold>23</jats:bold> and <jats:bold>26</jats:bold>; <jats:italic>Scheme 4</jats:italic>). The elucidation of the correct linkage of the spermine moiety with the aromatic dicarboxylic acid is based mainly on chemical and spectroscopic evidence of the tetrahydro derivative <jats:bold>26</jats:bold>, the <jats:italic>Hofmann</jats:italic>‐degradation products <jats:bold>28</jats:bold>, <jats:bold>30</jats:bold> and <jats:bold>31</jats:bold> (<jats:italic>Scheme 6</jats:italic>) as well as the ester <jats:bold>35</jats:bold>, prepared by partial hydrolysis of <jats:bold>2</jats:bold> (<jats:italic>Scheme 7</jats:italic>).