Fusicoccin ring system by [4+4] cycloaddition. 2. A model study

A synthetic approach to fusicoccin A utilizing intramolecular photocycloadd ition of tethered 2-pyridones has been completed. This study has led to the first solvent-dependent 2-pyridone photocycloaddition yielding either cis or trans products. Epoxidation of the cis photoproduct is selective for the disubstituted alkene, stabilizes the product, and is properly located for installation of the trans-1,2-diol. Activation of the secondary amide by re action with an isocyanate led to the reduction of the neopentyl amide carbo nyl to a methyl group. (C) 1999 Elsevier Science Ltd. All rights reserved.