Trihydroxypterocarpan dimethylallyltransferase (, glyceollin synthase, dimethylallylpyrophosphate:3,6a,9-trihydroxypterocarpan dimethylallyltransferase, dimethylallylpyrophosphate:trihydroxypterocarpan dimethylallyl transferase, dimethylallyl-diphosphate:(6aS,11aS)-3,6a,9-trihydroxypterocarpan dimethyltransferase) is an enzyme with systematic name dimethylallyl-diphosphate:(6aS,11aS)-3,6a,9-trihydroxypterocarpan dimethylallyltransferase. This enzyme catalyses the following chemical reaction
Part of the glyceollin biosynthesis system in soy bean.