Application of the efficient [4+4] photocycloaddition of 2-pyridones to two classes of natural products has been studied in model systems.  A sequence of [4+4] cycloaddition – [3,3] rearrangement – and retro-Mannich reactions assembles unsymmetrically coupled piperidines with predictable stereochemistry.  In a second model study, intramolecular [4+4] cycloaddition of a pyridone and a furan yields a pentacyclic cyclooctadiene.  The transannular cyclization of this intermediate was expected to give the tetraquinane framework of the crinipellins has led to several new reaction pathways for these strained photoadducts.