2,2,4-Trimethyl-3-hydroxy-3-pentenoic acid beta lactone 2,2-Dimethyl-3-isopropyliden-beta-propiolactone 2-Oxetanone, 3,3-dimethyl-4-(1-methylethylidene)- (9CI) 2-Oxetanone, 4-isopropylidene-3,3-dimethyl- 3-Hydroxy-2,2,4-trimethyl-3-pentenoic acid, beta-lactone 3-Pentenoic acid, 3-hydroxy-2,2,4-trimethyl-, beta-lactone 3173-79-3 4-Isopropylidene-3,3-dimethyl-2-oxetanone Dimethylketene dimer EINECS 221-643-5 NSC 74312