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Updated: Dec 17, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Semi-synthetic diversification of coronarin D, a labdane diterpene, under Ugi reaction conditions
Kollery S Veena1,2, Murikkinthara S Taniya2,3, Jaice Ravindran1,2
1Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, Kerala, India.
Abstract:
The prevalence of 5-hydroxydihydrofuran-2(3H)-one moiety in natural products is exploited for the first time using coronarin D, a labdane diterpene, to afford Ugi reaction product 1a and interrupted Ugi product 2a. The potential of the Ugi reaction was further extended to l-phenylalanine, 2-aminopyridine, and d-glucosamine, which afforded Ugi reaction products 3a-f, 4, and 5a-d, respectively. Cytotoxicity studies in RAW cells reveal that compounds 3e and 5b were non-toxic up to 50 µM, and these compounds were able to reduce the LPS stimulated NO production in RAW cells in par with the standard anti-inflammatory drug dexamethasone.
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