T. Koerner, R. Voll, E. S. Younathan
Dec 1, 1977
Citations
0
Influential Citations
33
Citations
Journal
Carbohydrate Research
Abstract
Abstract Acidic dehydration of D -mannitol ( 1 ) gave a mixture of anhydrides ( 2 ) that was isopropylidenated and subsequently tritylated. A single component crystallized from the resulting mixture and was shown to be the novel 2,5-anhydro-1,3- O -isopropylidene-6- O -trityl- D -glucitol ( 4 ) by chemical and physical analysis and by comparison of its deprotected, dibenzoylated derivative ( 10 ) with authentic 2,5-anhydro-1,6-di- O -benzoyl- D -glucitol. Acid hydrolysis of 4 afforded pure 2,5-anhydro- D -glucitol ( 9 ) in better yield than by the previously reported route. The 4- O -acetyl ( 5 ), 4- O -chloro-acetyl ( 6 ), 4- O -methyl ( 7 ), and 4- O -(methylsulfonyl) ( 8 ) derivatives of 4 , the tetra- O -acetyl ( 11 ) derivative of 9 , and the 3,4-di- O -acetyl ( 12 ) derivative of 10 , have been prepared and spectrally characterized. Complete proton-n.m.r. analysis yields first-order coupling constants that indicate the E 1 ( D ) conformation for the tetrahydrofuran ring and the chair conformation for the 1,3-dioxane ring of 4-2-8 . Obtainable coupling constants suggest that 11 and 12 exist in the o E and/or o T 1 , conformations.