Jacobine.

This alkaloid of the pyrrolizidine group of bases occurs in Senecio cineraria D.C., S. crucifolia and S. Jacobea. It is a laevorotatory base with [α]¹⁷_D - 46.3° (CHCl 3 ). The alkaloid forms crystalline salts and derivatives, e.g. the hydrochloride, m.p. 220°C; [α]¹⁹_D - 14.3° (H20); nitrate, m.p. 234°C; methiodide, m.p. 255°C and the picrate, m.p. 180°C which is soluble in H20. The alkaloid contains two active hydrogens and on alkaline hydrolysis yields retronecine and jaconecic acid, ClOH16 0 6, m.p. 182°C; [α]²⁵_D + 31.7° containing three O-methyl groups

Jacobine is a pyrrolizidine alkaloid which has been shown to be an herbivore insect deterrent and may be used in the protection of vegetation. Extracted from Crassocephalum plant of West Africa.

ChEBI: Jacobine is a pyrrolizine alkaloid.

Manske., Can. J. Res., 5,651 (1931)
Hosking, Brandt., New Zealand J. Sci. Tech., 14,638 (1936)
Blackie.,Pharrn. J., 138,102 (1937)
Barger, Blackie., J. Chern. Soc., 584 (1937)
Bradbury, Willis., Austral. J. Chern., 9,258 (1956)
Geissman., ibid, 12,247 (1959)
Bradbury, Masamune., J. Arner. Chern. Soc., 81,5201 (1959)
Masamune., ibid, 82, 5253 (1960)
Freidrichsons, Mathieson, Sutor., Tetrahedron Lett., 35 (1960)