From Rauwolfia sumatrana Jack (Apocynaceae) the two new indole alkaloids serpentinine and N(a)‐demethylseredamine were isolated. By chemical and spectroscopic evidence and by correlation experiments the latter was shown to have structure 2. the exact position of the aromatic methoxyl group was established by an investigation of the brominated derivative 12. The aromatic ORD. Cotton effect of N(a)‐acetyl‐N(a)‐demethyl‐seredamine (5) and its O‐acetyl derivative 4 as well as the ketone Cotton effect of purpeline (9) suggest that all the alkaloids of the seredamine group have the same absolute stereochemistry as ajmaline (1). This was confirmed by a direct chemical correlation of seredamine (7) with ajmaline. Copyright © 1970 Verlag GmbH & Co. KGaA, Weinheim