Zou, Bin; Chen, Chun; Leong, Seh Yong; Ding, Mei; Smith, Paul W. published an article on January 21 ,2014. The article was titled 《An efficient synthesis of 4,6-dihydrospiro[azepino[4,3,2-cd]indole-3,3′-indoline]-2′,5(1H)-diones via multi-component reaction》, and you may find the article in Tetrahedron.Electric Literature of C8H7FN2 The information in the text is summarized as follows:
A facile and efficient one-pot three-component synthesis of spiroazepinoindolones has been developed. Using DMF as solvent without any addnl. acid or metal catalysts, the three-component reaction of readily available isatins, indolamines, and Meldrum’s acid affords a new class of spiroheterocycles in moderate yield. In the experimental materials used by the author, we found 6-Fluoro-1H-indol-4-amine(cas: 885518-25-2Electric Literature of C8H7FN2)
6-Fluoro-1H-indol-4-amine(cas: 885518-25-2) belongs to anime. Nitrous acid converts secondary amines (aliphatic or aromatic) to N-nitroso compounds (nitrosamines): R2NH + HNO2 → R2N―NO. Some nitrosamines are potent cancer-inducing substances, and their possible formation is a serious consideration when nitrites, which are salts of nitrous acid, are present in foods or pharmaceutical preparations. Tertiary amines give rise to nitrosamines more slowly; an alkyl group is eliminated as an aldehyde or ketone, along with nitrous oxide, N2O.Electric Literature of C8H7FN2
Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles