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Novel base-initiated cascade reactions of hemiindigos to produce dipolar γ-carbolines and indole-fused pentacycles.

ABSTRACT: Novel continuous-flow cascade reactions are developed for producing 1,4-diaryl-disubstituted dipolar γ-carbolines 2 that contain a carboxylate group and their two pentacyclic precursors 6, 7 from hemiindigos 1. The nucleophilic and pro-electrophilic chemistry described is new to the hemiindigos 1, and it led to the discovery of antimycobacterial scaffold characteristic of rimino-type pentacycles 6, 7 and potent drug clofazimine. The new scaffold like clofazimine appears to be useful in developing lead agents active against drug-resistant/dormant TB.

SUBMITTER: Velezheva VS

PROVIDER: S-EPMC9076487 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Novel base-initiated cascade reactions of hemiindigos to produce dipolar γ-carbolines and indole-fused pentacycles.

Velezheva V S VS Babii O L OL Khodak A A AA Alekseeva E A EA Nelyubina Yu V YV Godovikov I A IA Peregudov A S AS Majorov K B KB Nikonenko B V BV

RSC advances 20191213 71

Novel continuous-flow cascade reactions are developed for producing 1,4-diaryl-disubstituted dipolar γ-carbolines 2 that contain a carboxylate group and their two pentacyclic precursors 6, 7 from hemiindigos 1. The nucleophilic and pro-electrophilic chemistry described is new to the hemiindigos 1, and it led to the discovery of antimycobacterial scaffold characteristic of rimino-type pentacycles 6, 7 and potent drug clofazimine. The new scaffold like clofazimine appears to be useful in developin ...[more]

PMID: 35541627

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