Total synthesis of (±)-quinolizidine 207I, an alkaloid from Mantella baroni, a Madagascan mantelline frog

Abstract

The first synthesis of quinolizidine 207I was achieved by a totally stereocontrolled approach starting from a 9-azabicyclo[3.3.1]nonane derivative, thus establishing the exceptional axial stereochemistry of the ethyl group at position 1.

References

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7. Selected data for 4: δ_H(400 MHz, CDCl₃) 0.88 (t, J 7.5, 3H; CH₃), 1.20–1.83 (m, 14H), 1.85–1.93 (m, 1H, CH), 1.97 (ddd, J 11.4, 2.6, 2.6, 1H; CH), 2.12–2.22 (m, 1H; CH), 2.44 (ddddd, J 14.2, 6.5, 3.2, 1.6, 1.6, 1H; CH), 3.32–3.38 (m, 1H; CH), 5.02–5.09 (m, 2H; CH₂), 5.85 (dddd, J 17.0, 10.3, 7.5, 6.7, 1H; CH); δ_C(100 MHz, CDCl₃) 12.45, 18.40, 24.99, 26.20, 26.26, 27.13, 31.01, 38.27, 40.56, 53.00, 64.13, 66.66, 115.88, 136.16.