Recent development in the synthesis of imidazo[1,5-a]indole derivatives: an in-depth overview
Elizabeth J Diana1,2, Jisna Jose1, Thomas V Mathew1
1Department of Chemistry, St Thomas College Palai, Arunapuram P.O., Kottayam, Kerala, 686574, India. majothomas@stcp.ac.in.
Abstract:
In the realm of nitrogen-fused heterocycles, imidazo[1,5-a]indole and its derivatives are recognized as privileged structural patterns in various pharmaceutical drugs and biologically active natural products, emphasizing their significance. This review comprehensively explores the synthetic strategies for constructing imidazo[1,5-a]indole scaffolds, with a particular focus on transition metal-catalyzed methodologies. The primary highlighted method is [4 + 1] annulation, along with other notable approaches such as C-H activation/cyclization, enantioselective C-H annulation, intramolecular hydroamination, and double cyclization processes.
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