The rate-correct score (RCS) metric was used to assess the speed-accuracy trade-off. RCS is the number of solved molecules divided by the summed search times, Ti. dUCT-v1 attained the highest RCS for all iteration values tested (Figure ). We conclude that 100 iterations are best for RCS. In time-based control testing (Table ) both eUCT and dUCT-v2 achieved higher solve percentages than UCT, with increases of 1.2%, 1.3%, and 0.8% for the respective time constraints (150, 100 and 60 s) for eUCT, and 1.6%, 1.5%, and 1.8% for dUCT-v2. For the test set of 50,000, this equates to between 400 and 900 more molecules. The preceding discussion gives a statistical analysis of the value of the enhancements. We now turn to an illustrative example: almotriptan, a molecule used as a medication for migraines. It belongs to a class of compounds known as triptans, which are serotonin receptor agonists. It contains a sulfonamide group which is essential for its biological activity. Almotriptan was used as an exemplar in a previous retrosynthesis study using Chematica (commercially available as SYNTHIA). A graph-based algorithm with shared information across targets was used to generate libraries of compounds or isotopically labeled molecules. The algorithm helps to improve the synthesis of multiple targets simultaneously. This method was used to design synthetic plans for isotopically labelled variants of almotriptan.