Forward reaction exploration with a modified Dijkstra algorithm. Naive complete exploration of the reaction network by applying the ERS to all products at each step (i.e., characterizing all ERS products of the ERS products ... of the ERS products of L-glucose) grows exponentially and makes deep exploration impossible. For example, complete b2f2 exploration of the unimolecular decomposition network of γ-ketohydroperoxide of depth of two already contains hundreds of intermediates, which is relatively simple compared with L-glucose. However, the number of kinetically relevant reactions in established reaction networks is linearly proportional to the number of intermediates, which suggests that the kinetically relevant sub-network only grows linearly rather than exponentially. One means of avoiding exploration of kinetically irrelevant pathways is to use an activation energy threshold and avoid further exploration downstream of a high-barrier reaction. However, this simple approach only reduces the base of the exponential scaling with network depth and is still impractical for deep exploration. Using thresholds that do not consider the whole network also neglects the possibility that a pathway that seems kinetically irrelevant might become relevant again if more severe bottlenecks are encountered downstream of the branching point.