Carbazole-5,7 -dione 5//-indolo pyrrolo

The UV spectrum [7max 238, 256 (sh), 293 (sh), 314, 362 (sh), and 390 (sh) nm] of rebeccamycin (337) indicated the presence of an indolo[2,3-fl]pyrrolo[3,4-c]carbazole-5,7(6H)-dione framework. This was also discernible from its IR spectrum. The H-NMR spectrum indicated the presence of an amide NH at 8 11.37 and an indole NH at 6 10.30, in addition to signals for aromatic protons and a sugar moiety. Unlike (+)-staurosporine (295) (see Scheme 2.74), where the lactam function deshielded only the ortho C-4 proton, the C-4 and C-8 aromatic protons in rebeccamycin are both deshielded due to the anisotropic deshielding effect of the phthalimide function. 

Indolo[2,3-a]pyrrolo[3,4-c)carbazole-5,7(6fl)-diones 44,946 Indolo[2,3-a]quinolizinium betaines 42,781s43... 

In addition to carbazoles, pyrrole ring-containing PAHs such as 7/f-indolo[2,3-clquinoline 9,1 l//-indolo[3,2-c]isoquinoline 11, 9/7-pyrrolo[2,3- 4,5-c ]dipyridine 13a, 9/7-pyrido[2,3- ]indole 13b, benzo[a]pyrrolo[3,4-c]carbazole-l,3-(2//,8//)-dione 15, and 6//-indolo[3,2-fe]benzo[fe]thiophene 17 were accessible by intramolecular direct arylation strategy (Scheme 22.4) [10]. The cyclization of 3-(2-bromophenylamino)quinoline 8 and 4-(2-bromophenylamino)isoquinoline 10 was catalyzed by Pd(PPh3)2Cl2 in the presence of NaOAc in DMA and reached to... 

Oxidative cyclization of bis(indolyl)maleimide 82 proceeded with the aid of Pd(OAc)2, CuCl2, and air, giving rise to 5//-indolo[2,3-a]pyrrolo[3,4-c]carbazole-5,7(6//)-dione 83 in high yield (Scheme 22.19) [40]. Functional groups such as... 

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