本酶催化的反应为4-Coumaroyl-CoA + A Flavonol 3-O-[beta-D-Glucosyl-(1->2)-beta-D-Glucosyl-(1->2)-beta-D-Glucoside] = CoA + A Flavonol 3-O-[6-(4-Coumaroyl)-beta-D-Glucosyl-(1->2)-beta-D-Glucosyl-(1->2)-beta-D-Glucoside],系统名称为4-Coumaroyl-CoA:flavonol 3-O-[beta-D-Glucosyl-(1->2)-beta-D-Glucosyl-(1->2)-beta-D-Glucoside] 6'''-O-4-Coumaroyltransferase,在末端葡萄糖基单元上酰化山柰酚3-O-三葡萄糖苷,几乎可以肯定在C-6位。