Copper-catalyzed synthesis and anticancer activity evaluation of indolo[1,2-a]quinoline derivatives

• Published in: Tetrahedron letters 2021-10, Vol.82, p.153365, Article 153365
• Main Authors: Thanetchaiyakup, Adisak, Borwornpinyo, Suparerk, Rattanarat, Hassayaporn, Kanjanasirirat, Phongthon, Jearawuttanakul, Kedchin, Seemakhan, Sawinee, Chuanopparat, Nutthawat, Ngernmeesri, Paiboon
• Format: Article
• Language: English
• Subjects: Indolo[1,2-a]quinoline; Knoevenagel condensation; One-pot synthesis; Ullmann-type reaction
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2021.153365

[Display omitted] •A simple one-pot synthesis of substituted indolo[1,2-a]quinolines.•A cascade reaction consisting of a Knoevenagel condensation reaction followed by an Ullmann-type coupling reaction.•Moderate to excellent yields (up to 98%).•Active against human breast and colorectal cancer cell lines. A simple and effective one-pot synthesis of substituted indolo[1,2-a]quinolines has been developed. The desired products were obtained in up to 98% yield when substituted 2-methyindoles were treated with 2-iodobenzaldehyde in the presence of Cs2CO3, CuI and l-proline. Our mechanistic study confirmed that the reaction sequence involved an intermolecular Knoevenagel reaction followed by an intramolecular Ullmann-type coupling reaction. Moreover, some of the synthesized compounds were found to be active against human breast (MCF-7) and colorectal (HCT-116) cancer cells with IC50 values of 27.96 μM and in the range of 6.21–46.91 μM, respectively.