1 AI2 3a-methyl-5,6-dihydro-furo[2,3-D][1,3,2]dioxaborole-2,2,6,6a-tetraol 1.000 2 A1B 1-deoxy-alpha-L-xylulofuranose-1,2-borate 0.923 3 A2B L-xylulofuranose-1,2-borate 0.857