Isatin reacted with diethyl 3-amino-2-cyano-2-pentenedioate in ethanol and in presence of Et₃N to give 3-(1-amino-2-cyano-2-ethoxycarbonylethenyl-2H-furo[2,3-b]indol-2-one. The reaction of (2-oxo-3-indolinylidene)malononitrile (3a) with the diethyl ester gave a mixture of diethyl 3-amino-4-(2-amino-3-cyano-4-quinolylcarbonyl)-2-cyano-2-pentenedioate (80%) and diethyl 3-amino-4-(2-amino-3-cyano-3aH-furo[2,3-b]indol-3a-yl)-2-cyano-2-pentanedioate (20%). Treatment of 3a and 3-[cyano(ethoxycarbonyl)]methylene-2-indolinone (3b) with 2-(ethoxycarbonylmethyl)-2-thiazolin-4-one gave the corresponding two pyrano[4′,5′-c] and furo[2″,3″-b]indole compounds, respectively. When 3a and 3b also reacted, with 3-methyl-2-pyrazolin-5-one or 3-methyl-1-phenyl-2-pyrazolin-5-one, the corresponding four spiro indoline-3,4′-(1′H)-pyrano[2,3-c]pyrazol products were obtained. The reaction of 3b with benzoylacetonitrile gave ethyl 2-amino-3a-[benzoyl(cyano)methyl]-3aH-furo[2,3-b]indole-3-carboxylate.