Fig. 5: Strategies and solution examples given by our system.

a A “complementary chain” (middle) is extracted from a synthesis route (top) and subsequently employed in a retrosynthesis task (bottom). This “complementary chain” involves the addition and elimination of BOC. The dashed arrow represents internal reactions between two complementary reactions. b A “cascade chain” (middle on the right), is extracted from the synthesis route (left). Two examples utilizing the “cascade chain” are indicated by the red and blue arrows, respectively. c An example of how a strategy expedites retrosynthetic planning. The top synthesis route is from the dataset, while the bottom is the route we find. Several steps highlighted by red dashed boxes are extracted as a new template, which is then used as indicated by the green arrow below. d Our method finds a shorter path because of a better selection in an intermediate step.