ABSTRACT
Experimental Methods ........................................................................................... 270 General Methods ............................................................................................... 270
6-O-Benzyl-1,2:3,4-Di-O-Isopropylidene-α-d-Galactopyranose (2) ........... 270 Methyl 2,3,5-Tri-O-Benzoyl-6-O-Benzyl-β-d-Galactofuranoside (4) ......... 270 1,6-Anhydro-2,3,5-Tri-O-Benzoyl-α-d-Galactofuranose (5) ....................... 271 1,6-Anhydro-α-d-Galactofuranose (6) ......................................................... 271 1,6-Anhydro-2,3,5-Tri-O-Acetyl-α-d-Galactofuranose (7).......................... 271
Acknowledgment ................................................................................................... 271 References .............................................................................................................. 274
6-O-Benzyl-1,2:3,4-di-O-isopropylidene-α-d-galactopyranose (2),1 prepared from 1,2:3,4-di-O-isopropylidene-α-d-galactopyranose (1),2 can be converted to a number of useful synthetic intermediates. p-Toluenesulfonic acid-catalyzed methanolysis gives methyl 6-O-benzyl-β-d-galactofuranoside (3), which can be readily benzoylated. The resulting methyl 2,3,5-tri-O-benzoyl-6-O-benzyl-β-d-galactofuranoside (4),1 when treated with stannic chloride in dichloromethane, gives 1,6-anhydro2,3,5-tri-O-benzoyl-α-d-galactofuranose (5)3 as the only product. Compound 5 can be further characterized by conversion to triol 6 and the triacetate 7.
