Acid-catalyzed conversion of mono- and poly-sugars into platform chemicals: Effects of molecular structure of sugar substrate

► Molecular structures determine reaction pathways of sugars during acid-treatments. ► Levulinic acid/ester yields: fructose > glucose > galactose ∼ levoglucosan. ► Reaction pathways for soluble polymer from fructose and glucose are different. ► Behaviors of poly-sugars were largely determined by their basic units. ► Steric hindrance negatively affects access of poly-sugars to catalytic sites.