.alpha.,.beta.-Isopropylideneglycerol 1,2-Isopropylideneglycerin 1,2-Isopropylideneglycerol 1,2-O,O-Isopropylideneglycerin 1,2-O-Isopropylideneglycerol 1,3-Dioxolane-4-methanol, 2,2-dimethyl- 100-79-8