1-Methoxy-1,3-cyclohexadiene was used in the following studies:Synthesis of tetracyclic polyhydroxyquinones via Diels-Alder reaction.Synthesis of tetra-ortho-substituted biaryls via Diels-Alder reaction.Synthesis of optically active form of dihydroisocoumarin fragment of the gastroprotective natural product AI-77-B, via regiospecific Diels-Alder reaction with an acetylenic ester derivative.