reaction explorations starting at these products for a fixed number of steps or until they connected with the forward network. Based on recent experimental work by Fang et al., the major products obtained from glucose pyrolysis at 350 • C are hydroxymethylfurfural (HMF, 20.0%), furfural (FF, 15.0%), hydroxyacetaldehyde (HAA, 13.5%). In addition, 3-(2H)-furanone (3FO, 5.0%), dihydroxyacetone (DHA, 3.9%) and 3-hydroxy-γ-butyrolactone (HBL, 3.4%) are also observed with lower yields (≤ 5%). Since the formation pathways of HAA and DHA were already established in the forward reaction exploration, backward explorations were performed for the remaining four products (Supporting information section 1). Backward reaction exploration successfully connected HMF, FF, and 3FO with the forward reaction network (Fig. , a specific discussion of the reaction pathways to the minor product HBL is provided in Supporting information Section 1).