1H-indole-1-carboxylic acid, 3-(1-cyano-2-methoxy-2-oxoethylidene)-6-(1,1-dimethylethyl)-2,3-dihydro-2-hydroxy-, methyl ester, (3Z)- InChI=1/C18H20N2O5/c1-18(2,3)10-6-7-11-13(8-10)20(17(23)25-5)15(21)14(11)12(9-19)16(22)24-4/h6-8,15,21H,1-5H3/b14-12 methyl (3Z)-6-tert-butyl-3-(1-cyano-2-methoxy-2-oxoethylidene)-2-hydroxyindoline-1-carboxylate