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A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

Synthesis, antioxidant and DNA cleavage activities of novel indole derivatives

J S Biradar1, B S Sasidhar, R Parveen

  • 1Central Research Lab, Department of Chemistry, Gulbarga University, Gulbarga, 585106 Karnataka, India. jsbiradar@yahoo.com

European Journal of Medicinal Chemistry
|July 3, 2010
PubMed

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All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for the...
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