(-)-3,9-Dihydro-2,3,3,9-tetramethylfuro[2,3-b]quinoline-4(2H)-one

Description

This furanoquinoline alkaloid has been obtained from the bark of the Australian tree Flindersia ifflaiana. It is obtained in the form of a colourless gum which cannot be crystallized. The alkaloid is laevorotatory with [α]²⁹_D~~9 - 0.6° or [α]²⁹_D~~o - 3.6° (c 8.0, MeOH). From aqueous solvents, a crystalline hydrate is formed, m.p. 62-3°C. The ultraviolet spectrum in MeOH shows absorption maxima at 215, 236, 309 and 320 mil with a shoulder at 251 and an inflexion at 298 mil. A yellow crystalline picrate is known, m.p. 207-9°C. The probable structure obtained from infrared and NMR spectra, and dependent upon analogy with other alkaloids of this type, has been confirmed by the total synthesis of the (±)-form, m.p. 128-9°C.

References

Bosson et al., Austral. 1. Chem., 16, 480 (1963) Total syn thesis: Chamberlain, Grundon., Tetrahedron Lett., 3547 (1967)