Transition-metal-free C–N and C–C formation: synthesis of benzo[4, 5]imidazo[1, 2-a]pyridines and 2-pyridones from ynones. Issue 9 (22nd March 2018)

• Record Type: Journal Article
• Authors: Teng, Qing-Hu; Peng, Xiang-Jun; Mo, Zu-Yu; Xu, Yan-Li; Tang, Hai-Tao; Wang, Heng-Shan; Sun, Hong-Bin; Pan, Ying-Ming
• Is Part Of: Green chemistry. Volume 20:Issue 9(2018)
• Page Start: 2007
• Page End: 2012
• Publication Date: 2018-03-22
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/c8gc00069g
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : We have developed a facile method for the synthesis of benzo[4, 5]imidazo[1, 2- a ]pyridines and 2-pyridones from readily available ynones and 2-methylbenzimidazoles or acetamides. Abstract : Herein, a transition metal-free and efficient cascade reaction of ynones with 2-methylbenzimidazoles under mild conditions has been revealed. This cascade reaction involved a Michael addition/intramolecular cycloaddition/dehydration and provided the desired benzo[4, 5]imidazo[1, 2- a ]pyridines in moderate to good yield. Furthermore, three benzo[4, 5]imidazo[1, 2- a ]pyridines (3d, 3i, and3q ) exhibited good activities against Hep-G2 (human liver cancer), T-24 (human bladder cancer cell), and SK-OV-3 (human ovarian cancer) cell lines with IC50 values in the range of 8.05–10.67 μmol L −1 . To investigate the mechanism of the effective inhibition of cell growth, further studies, including cell cycle analysis, apoptosis ratio detection, measurement of Ca 2+ generation, ROS, mitochondrial membrane potential assay, and caspase-3/9 activation, were carried out on compound3i .