Two azulene derivatives, 1-methoxycarbonyl-3-methylazulene (III) and 1-methoxycarbonyl-2- methylazulene (IV), were obtained by the pyrolysis of the photoproducts of methyl acetopyruvate-cycloheptatriene. IV was understood to be derived from a subsequent photo- pinacolization of an unisolable [2+ 2] π photoadduct (VIII).