Three‐component reactions of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione with malononitrile, or ethyl cyanoacetate, and cyclic six‐membered or a five‐membered 1,3‐diketone, produce spiro[4H‐pyran‐3,3′‐oxindoles].
Aldol condensation of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione with aryl methyl ketones generates 3‐(aroylmethylidene)oxindoles, which react with hydrazine to generate tricyclic spiro[3H‐pyrazole‐3,3′‐oxindoles].
The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione (1), reacts with a combination of an aryl cyanomethyl ketone 8 and a 5‐amino‐1‐arylpyrazole 7 to generate spirocyclic products 9.
The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione, undergoes three‐component, one‐pot reactions with 1‐aryl‐3‐methylpyrazole‐5‐amines and cyclohexane‐1,3‐diones producing hexacyclic spiro products, hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones]. Comparable spiro condensation products are also obtained using 4‐hydroxy‐2H‐1‐benzopyran‐2‐one in place of cyclohexane‐1,3‐diones.
It is a pleasure and privilege to take this opportunity to acknowledge the significant contributions to the chemistry of natural products by Professor Zbigniew Czarnocki and his Warsaw group
Knoevenagel condensation of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione 3 with aryl cyanomethyl ketones 9 generates 3‐(aroyl(cyano)methylidene)oxindoles 10 that react with cyclic 1,3‐diketones 11 to generate polycyclic hemiacetal spiro[4H‐2,3‐dihydropyran‐3,3′‐oxindoles] 13.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.