Current Organic Chemistry - Online First

Pyridines/Dihydropyridines is a basic 6-membered organic aza-heterocyclic compound that has garnered the attention of many researchers in recent times. These molecules have been reported with a diverse range of pharmacological activities like anti-coagulant, antileishmanial and anti-trypanosomal, antitubercular agents, anti-microbial, antioxidant, HIV-1 protease inhibitors, anti-cancer, cardiovascular disease, etc. This review article focuses on different protocols for the Hantzsch reaction using acid catalysts, metal catalysts, and no catalysts for the synthesis of pyridine derivatives. The structure-activity relationship in relation to other biological activities of various pyridine-containing drugs and their interaction with different targets (receptors) has also been highlighted to provide a good understanding to researchers for future research on pyridines.

Indoles are critical in natural amalgamation for their flexible jobs in drugs, regular items, and material science, exhibiting huge pharmacological and compound reactivity. Due to their versatility and high reactivity, nitroalkenes are essential electrophilic partners in organic synthesis. While indoles and nitroalkenes are used in both Michael addition and Friedel-Crafts alkylation for producing carbon-carbon bonds, the catalyst types and reactions involved are different. Michael addition employs conjugate addition, whereas Friedel-Crafts alkylation employs electrophilic aromatic substitution. Each technique has a different level of selectivity and distinct synthetic applications. This review examines the advancements and persistent challenges in catalysis, focusing on the comparative methodologies of Friedel-Crafts alkylation and Michael addition involving indoles and nitroalkenes. Emphasizing green chemistry principles, it discusses the potential for sustainable and efficient synthetic processes through the use of innovative catalysts, including photocatalysis and biocatalysis. The integration of computational studies and interdisciplinary collaboration is essential for developing economically viable and environmentally responsible chemical synthesis, ultimately contributing to the creation of advanced materials and pharmaceuticals.

Novel bispidine skeleton has been extensively designed as bifunctional chelators (BFCs) for their special stereochemical structure and variable dentate numbers. Bispidine-based ligands (BBLs) as BFCs generally integrate the benefits of conventional acyclic and macrocyclic BFCs, demonstrating exceptional radiolabeling kinetics, thermodynamic stability and kinetic inertness for their metal complexes. The accessible inherent spatial asymmetry in bispidine skeleton is well-suited for Jahn-Teller active metal ions, notably Cu(II). Currently, BBLs have already been studied to coordinate with radionuclides such as ⁵²Mn, ^64/67Cu, ⁶⁸Ga, ¹¹¹In, ¹³³La, ¹⁷⁷Lu, ²¹²Pb, ^212/213Bi, and ²²⁵Ac for radiopharmaceuticals application. Among them, the ⁶⁴Cu, ⁵²Mn, ¹¹¹In, ¹⁷⁷Lu, and ²²⁵Ac complexes with BBLs have particularly made significant research progress. In this review, we introduce the synthesis of BBLs and their applications in chelating the above five metallic radionuclides for the development of radiopharmaceuticals are discussed.

The Corona Virus Disease-19 (COVID-19) pandemic challenged the scientific community in the search for developing effective treatments, such as medicine and/or a vaccine candidate. The SARS-CoV-2 virus and its variants, Omega, Omicron, and Delta, remain as a major threat to human health, causing significant morbidity and mortality worldwide. Given that computational methods are thought to be quick, easy, and inexpensive, they have been widely used in this scenario to design new anti-COVID-19 drug candidates. In addition, heterocyclic scaffolds have been explored exhaustively for their biological properties and as fruitful sources of new molecular entities to fulfill the chemical space available.In light of this, we intend to highlight the synthetic techniques used to produce novel heterocyclic derivatives that may serve as effective anti-COVID-19 lead candidates by focusing on important viral proteins and using computational tools. Then, the objective of this article, with a theoretical nature, is to contribute to the delimitation of organic chemistry methods to achieve new anti-COVID-19 agents.