Fig. 2From: Molecular structures enumeration and virtual screening in the chemical space with RetroPath2.0Identical rules. There are two different ways (two different possible matchings for the reactants of the rules) of applying rules R a and R b, each rule produces molecules M1 and M2. The molecules produced by R a are identical to those produced by R b because the rules are identical. R a is identical to R b because when applying the one-to-one label mapping π(1, 2 , 3, 4) = 2, 1, 4, 3 on the edges of the R a one obtains the edges of R b Back to article page