SIMPLE SYNTHESIS OF 2,2'-BISINDOLE FROM INDIGO AND ITS APPLICATION FOR THE SYNTHESIS OF INDOLOPYRROLOCARBAZOLE-5,7-(6H)DIONE AND 5-(6H)ONE DERIVATIVES

Article abstract of DOI:10.3987/COM-95-7192

Indigo was converted to 2,2'-bisindole, from which 6-substituted indolo<2,3-a>pyrrolo<3,4-c>carbazole-5,7-(6H)dione and -5-(6H)one derivatives were prepared in short steps.Bromination of 6-methylindolo<2,3-a>pyrrolo<3,4-c>carbazole-5,7-(6H)dione is also r