The primary product of this enzyme is 4,2',4',6'-tetrahydroxychalcone (also termed naringenin-chalcone or chalcone) which can under specific conditions spontaneously isomerize into naringenin. 4-coumaroyl-CoA + 2 H(+) + 3 malonyl-CoA = 2',4,4',6'-tetrahydroxychalcone + 3 CO2 + 4 CoA Secondary metabolite biosynthesis; flavonoid biosynthesis. By wounding and Rhizobium infection. Belongs to the thiolase-like superfamily. Chalcone/stilbene synthases family.