6,10-Dioxaspiro(4.5)decane, 8,8-dimethyl- 702-75-0 8,8-Dimethyl-6,10-dioxaspiro(4.5)decane AI3-22869 Cyclopentanone, 2,2-dimethyl-1,3-propanediol ketal EINECS 211-869-2 NSC 7004