LOBININE

Description

A further alkaloid obtained from Lobelia inj1ata L., the base has not yet been obtained in a crystalline form. The hydrochloride forms colourless needles from either Et20-EtOH or Me2CO-EtOH, m.p. 144°C; [α]_D - 106.1° (H20) or- 130° (EtOH); the hydriodide, m.p. 130°C, perchlorate, m.p. 146°C and the platinichloride which decomposes, without melting, at 190°C. The oxime and the benzoyl derivative yield crystalline hydrochlorides with m.p. 182°C and 146-7°C respectively. Reduction with sodium amalgam in AcOH gives the unsaturated dihydric alcohol, the original name of '10 binoI' having now been altered to a-lo binanidine. Hydrogenation of the hydriodide in MeOH with Pt02 as catalyst, yields alelobanidine. Chromic acid oxidation gives initially lobinanine and acetic and benzoic acids, although under mild conditions at 100°C in dilute H2S04 it furnishes benzoic acid and lobininic acid, C9H130 4N, m.p. 207-8°C.

References

Wieland, Ishimasa, Koschara., Annalen, 491, 14 (1931)
Wieland et aI., ibid, 540, 103 (1939)