Catalyst and Solvent Free Synthesis and Biological Activities of Imidazo[1,2-a]pyridine

Abstract

A series of imidazo[1,2-a]pyridines were synthesized by the reaction of α-chloroacetophenone and 2- aminopyridine under catalyst and solvent free condition. The synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral data. These imidazo[1,2-a]pyridines were screened for antiinflammatory activity by carrageenan induced rat hind paw edema model. Good anti-inflammatory activity was shown by few compounds. The antibacterial activity was studied against two Grampositive bacteria S. aureus and B. subtilis, two Gram-negative bacteria E. coli and S. typhi and antifungal activity against P. chrysogenum, F. moneliforme, A. flavus and A. niger. All the synthesized compounds were desplayed good antimicrobial and antifungal activities. Some of the compounds were shown higher antibacterial activity than reference drug penicillin.

Crystal structure and Hirshfeld surface analysis of 2-oxo-2-phenylethyl 3-nitroso-2-phenylimidazo[1,2-a]pyridine-8-carboxylate

“…Numerous drugs contain N-heterocycles as the core structure, including imidazo[1,2-a]pyridine and its derivatives, which are used in medicinal chemistry (Swainston Harrison & Keating, 2005;Deep et al, 2017) or that exhibit diverse biological properties, such as antibacterial (Mishra et al, 2021), antitubercular (Wang et al, 2019), tyrosinase inhibitory (Damghani et al, 2020), HIV inhibitory (Bode et al, 2011), antidiabetic (Saeedi et al, 2021), anti-inflammatory (Gundlewad et al, 2020) or anticancer activities (Yu et al, 2020;Sigalapalli et al, 2021). Encouraged by these features and in a continuation of our exploration of the synthesis, molecular structures and Hirshfeld surface analysis of new Nheterocyclic compounds (Daoui et al, 2021(Daoui et al, , 2022El Kalai et al, 2021a,b), we report herein the crystal structure and Hirshfeld surface analysis of 2-oxo-2-phenylethyl 3-nitroso-2phenylimidazo[1,2-a]pyridine-8-carboxylate, C 22 H 15 N 3 O 4 (I).…”

Recent Advances in Transition-Metal-Free Late-Stage C-H and N-H Arylation of Heteroarenes Using Diaryliodonium Salts

“…Eco-friendly late-stage C-H functionalization of these N -bearing polycyclic scaffolds has emerged as a powerful strategy for the synthesis of libraries of highly valuable compounds. Indeed, 3-substituted imidazo[1,2- a ]pyridines are attractive compounds in drug development exhibiting various pharmacological activities as well as in optoelectronic devices [ 65 , 66 , 67 ]. The direct C3-arylations were performed in the presence of t BuOK (2.0 equiv) as a base in acetonitrile at 60 °C for 24 h ( Scheme 7 ).…”