K. Ando, T. Tokoroyama, T. Kubota
Apr 1, 1974
Citations
0
Influential Citations
5
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
The structure of 5-amino-4,7-dimethoxy-11H-indeno-[1,2-c]isoquinolin-11-one (2) derived by the degradation of the “red pigment” has been confirmed by synthesis. 5,6-Dihydro-4,7-dimethoxy-11H-indeno[1,2-c]isoquinoline-5,11-dione (3) obtained from 2 was used as a relay compound. This was first converted into 2 by chlorination with phosphorus oxychloride and treatment with ammonia. Subsequently 3 was synthesized from 2-(2-carboxy-3-methoxyphenyl)-4-methoxyindane-1,3-dione (13) via 4,7-dimethoxy-11H-indeno[1,2-c]isocoumarin-11-one (12).