Synthesis of 1′,6′-disubstituted sucroses and their behavior as glucosyl donors for a microbial α-glucosyltransferase

Versatile 6′-chloro-6′-deoxy-1′-substituted sucrose derivatives were synthesized in search of an optimum donor substrate for the intermolecular transglucosylation with the α-glucosyltransferase from Protaminobacter rubrum. Two substituents at the C-1′ and C-6′ positions of sucrose were introduced utilizing the distinct reactivity of the corresponding sulfonates. Methyl β-d-arabinofuranoside was most efficiently glucosylated with the 1′-deoxy derivative 5. Hydroxyl and fluoro groups at C-1′ show a tendency to enhance the intramolecular transglucosylations, giving 3-O-(α-d-glucopyranosyl)-d-fructose derivatives.