InChI=1S/C22H20O4S/c1-2-21(17-9-5-3-6-10-17)22(18-11-7-4-8-12-18)19-13-15-20(16-14-19)26-27(23,24)25/h3-16H,2H2,1H3,(H,23,24,25)/q-1/p-1/b22-21-