InChI=1S/C32H28O4/c33-26(18-16-23-10-4-1-5-11-23)20-28-21-29(25-14-8-3-9-15-25)31-30(35-28)22-27(36-32(31)34)19-17-24-12-6-2-7-13-24/h1-15,17,19,22,28-29H,16,18,20-21H2/b19-17+/t28-,29-/m1/s1