3-Aryl-substituted imidazo[1,2-a]pyridines as antituberculosis agents

Directed regioselective arylation of imidazo[1,2-a]pyridine-3-carboxamides using Rh(III) catalysis

In contrast to previously reported free-radical pathways to functionalize imidazo[1,2-a]pyridines at the C-5 centre, directing group approaches are rare. Herein, we demonstrate a rhodium(III) catalyzed efficient and regioselective strategy for directed C-5 functionalization of imidazo[1,2-a]pyridines using N-methoxyamide as a directing group. This methodology facilitates directed arylation without the necessity for pre-functionalization. It also allows for gram-scale synthesis and post-functionalization.

Insights into medicinal attributes of imidazo[1,2-a]pyridine derivatives as anticancer agents

Cancer ranks among the most life-threatening diseases worldwide and is continuously affecting all age groups. Consequently, many research studies are being carried out to develop new cancer treatments, but many of them experience resistance and cause severe toxicity to the patients. Therefore, there is a continuous need to design novel anticancer agents that are target-based, have a higher potency, and have minimal toxicity. The imidazo[1,2-a]pyridine (IP) pharmacophore has been found to be a prominent moiety in the field of medicinal chemistry due to its vast biological properties. Also, it holds immense potential for combating cancer with minimal side effects, depending on the substitution patterns of the core structure. IPs exhibit significant capability in regulating various cellular pathways, offering possibilities for targeted anticancer effects. The present review summarizes the anticancer profile of numerous IP derivatives synthesized and developed by various researchers from 2016 till now, as inhibitors of phosphoinositide-3-kinase/mammalian target of rapamycin (PI3K/mTOR), protein kinase B/mammalian target of rapamycin (Akt/mTOR), aldehyde dehydrogenase (ALDH), and tubulin polymerization. This review provides a comprehensive analysis of the anticancer activity afforded by the discussed IP compounds, emphasizing the structure-activity-relationships (SARs). The aim is also to underscore the potential therapeutic future of the IP moiety as a potent partial structure for upcoming cancer drug development and to aid researchers in the field of rational drug design.

Imidazo[1,2-A]Pyridine: Potent Biological Activity, SAR and Docking Investigations (2017-2022)

BACKGROUND

Regarding scientific research, Imidazo[1,2-a] pyridine derivatives are constantly being developed due to the scaffold's intriguing chemical structure and varied biological activity. They are distinctive organic nitrogen-bridged heterocyclic compounds that have several uses in medicines, organometallics and natural products. It has become a vital tool for medicinal chemists.

METHODS

In order to gather scientific information on Imidazo[1,2-a] pyridines derivative, Google, PubMed, Scopus, Google Scholar, and other databases were searched. In the current study, the medicinal value and therapeutic effect of Imidazo[1,2-a] pyridines were investigated using above mentioned databases. The current study analyzed the detailed pharmacological activities of Imidazo[1,2-a] pyridine analogs through literature from diverse scientific research works.

RESULTS

Due to its wide range of biological activities, including antiulcer, anticonvulsant, antiprotozoal, anthelmintic, antiepileptic, antifungal, antibacterial, analgesic, antiviral, anticancer, anti-inflammatory, antituberculosis, and antitumor properties, imidazopyridine is one of the most significant structural skeletons in the field of natural and pharmaceutical products. An imidazopyridine scaffold serves as the basis for a number of therapeutically utilized medications, including zolpidem, alpidem, olprinone, zolimidine, and necopidem.

CONCLUSION

This comprehensive study covers the period of the last five years, and it sheds light on the developments and emerging pharmacological actions of Imidazo[1,2-a] pyridines. Additionally, the structure-activity relationship and molecular docking studies are carefully documented throughout the paper, providing medicinal chemists with a clear picture for developing new drugs.

Synthesis, molecular modeling Insights, and anticancer assessment of novel polyfunctionalized Pyridine congeners

The present study describes synthesizing a novel series of polyfunctionalized pyridine congeners 1-18 and assessed for cytotoxic efficacies versus HCT-116, MCF-7, and HepG-2 among one non-cancerous BJ-1 human normal cell. Most compounds were precisely potent anticancer candidate drugs. The molecular impact of the most active compounds 9, 10, 11, 13, 15, and 17 was evaluated after MCF-7 treatment. The gene expression of pro- and ant-apoptosis markers P53, Bax, Caspase-3 and Bcl-2 as well as VEGFR-2 and HER2 were determined. Compounds 13 and 15 induced upregulation of pro-apoptosis of P53, Bax, Caspase-3 and downregulation of anti-apoptosis Bcl-2 gene. However, compound 15 showed higher effect compared to 13 and respective control. Moreover, a slight reduction in HER2 gene expression was detected due to compound 15 treatment, while VEGFR-2 gene was upregulated. In agreement, the immunoblotting analysis showed higher accumulation of P53, Bax, Caspase-3 proteins and of decrease the Bcl-2 protein levels. Furthermore, docking studies united with molecular dynamic simulation exposed compounds 13 and 15 fitting in the middle of the active site at the interface linking the ATP binding site and the allosteric hydrophobic binding pocket. Finally, we performed Petra/Osiris/ Molinspiration (POM) analysis for the newly synthesized compounds. The evaluation of primary in silico parameters revealed significant differences among individual polyfunctionalized pyridine compounds, highlighting the most promising candidates. These preliminary results may help in coordinating and initiating other research projects focused on polyfunctionalized pyridine compounds, especially those with predicted bioactivity, low toxicity, optimal ADME parameters, and promising perspectives.

Recent developments of imidazo[1,2-a]pyridine analogues as antituberculosis agents

Over the past 2000 years, tuberculosis (TB) has killed more people than any other infectious disease. In 2021, TB claimed 1.6 million lives worldwide, making it the second leading cause of death from an infectious disease after COVID-19. Unfortunately, TB drug discovery research was neglected in the last few decades of the twentieth century. Recently, the World Health Organization has taken the initiative to develop new TB drugs. Imidazopyridine, an important fused bicyclic 5,6 heterocycle has been recognized as a "drug prejudice" scaffold for its wide range of applications in medicinal chemistry. A few examples of imidazo[1,2-a]pyridine exhibit significant activity against multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB). Here, we critically review anti-TB compounds of the imidazo[1,2-a]pyridine class by discussing their development based on the structure-activity relationship, mode-of-action, and various scaffold hopping strategies over the last decade, which is identified as a renaissance era of TB drug discovery research.

Copper-catalyzed three-component reaction to synthesize polysubstituted imidazo[1,2-a]pyridines

An efficient three-component one-pot and operationally simple cascade of 2-aminopyridines with sulfonyl azides and terminal ynones is reported, providing a variety of polysubstituted imidazo[1,2-a]pyridine derivatives in moderate to excellent yields. In particular, the reaction goes a through CuAAC/ring-cleavage process and forms a highly active intermediate α-acyl-N-sulfonyl ketenimine with base free.

Three-component one-pot synthesis of polysubstituted imidazo[1,2-a]pyridine derivatives through a base free CuAAC/ring-cleavage process.