Symmetrically and unsymmetrically 6,12-disubstituted 5,11-dihydroindolo[3,2-b]carbazoles have been synthesized via a range of methods: a) double Fischer indolization of the bis-phenylhydrazone of 2,5-dimethyl-1,4-cyclohexanedione, b) condensation of indole with aliphatic aldehydes, and c) Pd-mediated cyclization of a diphenyl phenylenediamine derivative. Most notably, 5,11-dihydroindolo[3,2-b]carbazole-6,12-dicarbaldehyde has been synthesized, whereby a previously assigned structure has been confirmed. This compound is an extremely efficient ligand for the TCDD (Ah) receptor.

中文翻译：

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6,12-二取代的5,11-二氢吲哚并[3,2- b ]咔唑的合成，包括5,11-二氢吲哚并[3,2 - b ]咔唑-6,12-二甲醛是一种非常有效的TCDD配体（ Ah）受体

通过一系列方法合成了对称和不对称的6,12-二取代的5,11-二氢吲哚并[3,2- b ]咔唑：a）2,5-二甲基-1,4的双-苯基hydr的双费歇尔吲哚化-环己二酮，b）吲哚与脂族醛的缩合，和c）Pd介导的二苯基苯二胺衍生物的环化。最显着地，已经合成了5，11-二氢吲哚并[3，2- b ]咔唑-6，12-二甲醛，由此证实了先前指定的结构。该化合物是TCDD（Ah）受体的极其有效的配体。