InChI=1/C11H9NO3/c1-15-10(13)6-8-7-4-2-3-5-9(7)12-11(8)14/h2-6H,1H3,(H,12,14)/b8-6 acetic acid, (1,2-dihydro-2-oxo-3H-indol-3-ylidene)-, methyl ester, (2Z)- methyl (2Z)-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)acetate