Provided are 5-acetoxy–3-pentenyl methoxymethyl ether which can be prepared in conventional reaction equipment and a method for preparing an -3-alkenyl acetate by using it. The user identity card is initially activated with the network. The enhanced content data is stored in a web browser cache. A diffusion barrier layer is also formed on the lower electrode and then a dielectric layer is formed on the diffusion barrier layer. More particularly, the present invention relates to a synergistic combination of a selective inhibitor of the neuronal norepinephrine transporter and an analgesic agent in the therapeutic management of vertebrate animals, including humans, for producing analgesia or for the prevention or alleviation of pain.