Applying these for consistency left a total of 355 edges. Finally excluding all transformations not resulting in a path executable in four steps or less left a total of 116 edges of interest. The 16 most highly scoring of these can be found in Figure and. Closer investigation revealed that at least 15 of the 116 transformations (and 52 of the 355 transformations) were correct predictions, known to Reaxys but not contained in this dataset. A selection can be found in Figure . Expanding the search set to five-step paths will require evaluation of more than 20,000 transformations. Clearly further heuristics are required to decide which transformations might merit a closer investigation. A first question is which transformations would be of value chemically. Obviously of interest here would be a transformation that turns a less reactive functional group into a reactive one as it increases the molecule's "synthetic value" by opening it up for further transformations. In our case study a transformation pattern found repeatedly is the conversion of a less reactive group into a highly reactive amine, as is the case in the reactions 40, 62, or 110 shown in Figure . Of similar value would be a transformation making a promising, new feedstock accessible. A number of proposed transformations are suggesting the use of thymol, which can be sourced sustainably, as reactant. Transformations that use thymol are reactions 3, 18, 21, 38 and 57 (the first three can be found in Figure and the last two in Figure ), which also represent transformations deemed most probable by the algorithm.