spiroadamantyl dioxetanes bearing an alkoxy substituent , and an aromatic substituent of phenyl or naphthyl on the dioxetane ring can be activated to chemiluminesce if the aromatic substituent bears a moiety designated ox , wherein the x is cleaved by an enzyme with which the dioxetane is permitted to come in contact with . the t 1 / 2 kinetics of the chemiluminescent reaction , as well as the signal intensity , or quantum yield of the chemiluminescent reaction , can be altered by selection of an electron - withdrawing or an electron - donating group z , at positions on the aromatic substituent other than those adjacent the point of attachment to the dioxetane . signal strength can further be enhanced by recognized chemiluminescent enhancers .