Reaction of sugars with Meldrum's acid: A route to 3,6-anhydro-2-deoxyaldono-1,4-lactones

Reactions between Meldrum's acid (2,2-dimethyl-1,3-dioxane-4,6-dione) and d -xylose, d -glucose, and d -galactose gave mainly 3,6-anhydro-1,4-lactones together with α,β-unsaturated-1,4-lactones. The preparation of 3,6-anhydro-1,4-lactones having the d - xylo , d - gluco , and d - galacto configurations is described.