An Asymmetric Synthesis of (+)-Erysotramidine

Abstract

A new asymmetric total synthesis of the erythrinan alkaloid erysotramidine is described, which uses chiral base desymmetrisation, N-acyliminium addition, and 6-exo-trig radical cyclisation as the key steps.

Key words

alkaloid - asymmetric synthesis - radical reaction - chiral base - erythrinan

References

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14

Our specific rotation data for 15 and 2 are not as high as those recorded previously, even taking into account that our material is ca. 92% ee. We attribute this to the presence of extremely low levels of highly optically active contaminants formed following the SeO₂ oxidation.