Upon irradiation, photosubstrates 1 and 3 give products 2 and 4 respectively, the results of a "crossed" [2+2] photocycloaddition.  However, allene-containing photosubstrate 5 gives the pyrrole-containing product 6 upon irradiation, the result of a "straight" photocycloaddition to the terminus of the allene.  The crossed photocycloaddition is currently being applied to studies directed toward the total synthesis of the Aristotelia alkaloid peduncularine while the straight photocycloaddition has been applied to the synthesis of novel pyrrole - containing structures.