“…Di- d -fructose dianhydrides (DFAs) comprise a diverse family of mono- or dispirocyclic acetals obtained by condensation of two fructose molecules, with formation of two reciprocal glycosidic linkages. Their basic mono- or bis-spiroketal framework resembles that found in many relevant natural products, including steroidal saponins, polyether ionophores, macrolide antibiotics, insect pheromones, and toxic metabolites from algae and fungi [ 1 , 2 , 3 , 4 , 5 ], and is the target of much synthetic effort [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. DFAs are formed upon thermal and/or acidic activation of sucrose- and/or d -fructose-rich materials.…”