Progress towards viridin: synthesis of the pentacyclic furanosteroid ring system via o-benzoquinonoid cycloadditions

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Fabio E. S. Souza and Russell Rodrigo


Abstract

The pentacyclic ring system of viridin is synthesised in nine steps from 4-methylguaicol by means of successive cycloadditions involving o-benzoquinonoid intermediates generated in situ.


References

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  15. Selected data for 7: δH(500 MHz, CDCl3) 1.51 (s, Me), 2.18 (dd, J 17.8, 3.1, H-1α), 2.67 (m, H-15), 2.74 (dd, J 17.8, 2.3, H-1β), 3.67 (m, H-16), 4.00 (app dt, J 10.3, 2.6, H-4), 4.06 (dd, J 10.7, 8.1, H-20α), 4.87 (dd, J 9.8, 8.1, H-20β), 5.74 (app s, H-2, H-3), 7.55 (d, J 8.1, H-11), 7.89 (d, J 8.1, H-12). Full details will be published later.
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