InChI=1S/C28H22O9S/c29-20-7-2-16(3-8-20)1-4-18-11-23(32)15-25-26(18)27(19-12-21(30)14-22(31)13-19)28(36-25)17-5-9-24(10-6-17)37-38(33,34)35/h1-15,27-32H,(H,33,34,35)/b4-1-