1,5-Dioxaspiro(5.5)undecane, 3,3-dimethyl- 3,3-Dimethyl-1,5-dioxaspiro(5.5)undecane 707-29-9 AI3-22819 Cyclohexanone, 2,2-dimethyl-1,3-propandiol ketal EINECS 211-898-0 NSC 7021