pterocarpans Members of the class of benzofurochromene with a 6a,11a-dihydro-6H-[1]benzofuro[3,2-c]chromene skeleton and its substituted derivatives. They generally bear structural resemblance to isoflavanoids that possess antibiotic activity and are produced by plant tissues in response to infection. They are the 3,4-dihydroderivatives of coumestans. isoflavonoid