for the following products
1,2:5,6-di-O-isopropylidene-alpha-D-ribo-hexofuranose-3-ulose | 1,2:5,6-Di-O-isopropylidene-alpha-D-ribo-hexofuranose-3-ulose (mixture of keto and ketal forms) | 1,2:5,6-di-O-isopropylidene-α-D-hexofuran-3-ulose and 1,2:5,6-di-O-Isopropylidene-alpha-D-ribohexulofuranos-3-ulose
