Konstitution von Palustridin

Palustridine (I, C 18 H 31 N 3 O 3 ), which co‐occurs with palustrine in Equisetum palustre L., has been shown to be N b ‐formyl‐palustrine. Hydrolysis with dilute mineral acid yields palustrine, and formylation of the latter gives palustridine. The mass spectral fragmentation pattern differs from that of palustrine, and is very similar to that of N b ‐acetylpalustrine. The earlier proposed skeleton of palustrine is independently confirmed.