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Regioselective Ring Expansion of Isatins with In Situ Generated α-Aryldiazomethanes: Direct Access to Viridicatin Alkaloids

Yellaiah Tangella, Kesari Lakshmi Manasa, Namballa Hari Krishna, B. Sridhar, Ahmed Kamal* and Bathini Nagendra Babu*

*Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025; CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India, Email:,

Y. Tangella, K. L. Manasa, N. H. Krishna, B. Sridhar, A. Kamal, B. N. Babu, Org. Lett., 2018, 20, 3639-3642.

DOI: 10.1021/acs.orglett.8b01417

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An efficient one-pot regioselective ring-expansion reaction of isatins with in situ generated α-aryl/heteroaryldiazomethanes enables the construction of viridicatin alkaloids under metal-free conditions, including the naturally occurring viridicatin, viridicatol, and substituted 3-O-methyl viridicatin.

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proposed mechanism

Key Words


ID: J54-Y2018