A pyrrolizidine alkaloid first isolated from Crotalaria usararnoensis E. G. Baker,
this base has more recently been found in C. brevifolia and C. rnucronata. The
alkaloid has [α]20D + 6.1° (c 0.38, EtOH) or + 7.1° (c 1.83, EtOH). It yields a
picrate, m.p. 230- 2°C (dec.); picrolonate, m.p. 148-150°C (dec.); reineckate,
m.p. 190-2°C (dec.) and methiodide, m.p. 229-230°C (dec.). Alkaline
hydrolysis furnishes retronecine and retronecic acid, m.p. 177-9°C. It has been
suggested that the base may be identical with Mucronatine (q.v.).
Culvenor, Smith., Austral. J. Chern., 19,2127 (1966)
Sawhney et al., Ind. J. Chern., 5, 655 (1967)