Photocycloaddition in natural product synthesis

The application of photocycloaddition to natural product synthesis continues to produce innovative and effective strategies for key bond constructions in the complex molecule environment. This Microreview surveys the recent literature for examples that illustrate the power and versatility of photocycloaddition chemistry, drawing from [2+2], [3+21, [4+2], [5+2] and [4+4] reactions. The discussion is confined to natural product syntheses, and will include photocyclo addition key steps in both completed routes and those in progress.