2,3:4,5-bis-O-(1-methylethylidene)-β-L-Fructopyranose chlorosulfate; 5H-Bis[1,3]dioxolo[4,5-b:4′,5′-d]pyran, β-L-fructopyranose deriv; 2,3:4,5-Bis-O-(1-methylethylidene)-β-L-fructopyranose sulfonyl chloride; ((3aR,5aS,8aS,8bR)-2,2,7,7-tetramethyltetrahydro-3aH-bis([1,3]dioxolo)[4,5-b:4',5'-d]pyran-3a-yl)methyl sulfochloridate,Topiramate Impurity