Sequential Annulations to Interesting Novel Pyrrolo[3,2-]carbazoles.

Molecules

Department of Chemistry and Industrial Chemistry, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy.

Published: October 2019

Herein we report a significant, valuable extension of a recently implemented pyrrole benzannulation methodology that, employing versatile nitrodienes from our lab as useful C building blocks, led to indole derivatives characterized by unusual patterns of substitution. The 6-nitro-7-arylindoles resulting from suitably derivatized, non-symmetric dienes are of foreseeable synthetic interest in search for new polyheterocyclic systems. As an example, pyrrolocarbazoles with a rarely reported ring fusion were synthesized with the classical Cadogan protocol. Furthermore, the proven easy reducibility of the nitro group to amine will surely open the way to further interesting elaborations.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832463PMC
http://dx.doi.org/10.3390/molecules24203802DOI Listing

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