Indoloquinolines, Indolobenzoxazines and Quinazolophthalazines Prepared from Norbornane/eneamino Acids and Hydrazides

The reactions of di-endo- and di-exo-aminonorbornane/enecarboxylic acids 1–4 with ethyl 2-(2-oxocyclohexyl)acetate afforded methanoindoloquinolines 5, 6, 8, and 9, the oxo ester participating as a two-membered sp2 building block. In the cases of di-exo- and di-endo-aminonorbornenecarboxylic acids 2 and 4, methanoindolobenzoxazinediones 7 and 10 were also formed; compound 7 was also isolated from the mother liquor of 10. The reactions of ethyl 2-(2-oxocyclohexyl)acetate with aminonorbornane/enecarbohydrazides 11–14 result in the methanoquinazolophthalazines 15–18. The structures of the compounds were elucidated by NMR spectroscopy, and for 6, 7, 8, and 10 also by X-ray crystallography. (© Wi…