bisadduct noun1 •The product of two simultaneous addition reactions on the same moleculeAldrichimica Acta Volume 30 No 4 (pdf) from Sigma-Aldrich Both π-bonds in 42 react with DMAD in the presence of a Ru-catalyst to produce bisadduct 43; this is the first example of a cyclobutene π-bond reacting in this fashion. formsbisadducts