Iodine-catalyzed electrophilic substitution of indoles: Synthesis of (un)symmetrical diindolylmethanes with a quaternary carbon center

• Thanigaimalai Pillaiyar,
• Masoud Sedaghati,
• Andhika B. Mahardhika,
• Lukas L. Wendt and
• Christa E. Müller

Beilstein J. Org. Chem. 2021, 17, 1464–1475, doi:10.3762/bjoc.17.102

• , and scalability to obtain gram amounts for biological studies. Selected compounds were found to display affinity for cannabinoid receptors, which are promising drug targets for the treatment of inflammatory and neurodegenerative diseases. Keywords: alkylation of indole; anti-inflammatory; binding

• affinity; cannabinoid receptors; diindolylmethane; unsymmetrical 3,3'-diindolylmethane; Introduction Diindolylmethanes (DIMs) represent an important class of indole alkaloids, that are constituents of pharmaceuticals [1][2][3][4][5][6][7] and agrochemicals [8][9]. DIM derivatives possess a variety of

• previously reported to bind to the cannabinoid receptors, CB1 (Ki 4.3 µM) and CB2 (Ki 1.1 µM) [41]. Both receptors are considered important therapeutic targets, e.g. for neurodegenerative and inflammatory diseases. Selected final products (3a, 3b, 3e, 3g, 3h, 3n, 3ad) were tested for their binding affinities