Inhibiting Excessive Molecular Aggregation to Achieve Highly Efficient and Stabilized Organic Solar Cells by Introducing Star-Shaped Nitrogen Heterocyclic-Ring Acceptor

Inhibiting excessive aggregation and migration of active layer molecules is essential to improve the stability and performance of organic solar cells (OSCs). Herein, the star-shaped nitrogen heterocyclic-ring acceptor TF1 featuring...

Recent developments in the synthesis of five- and six-membered N-heterocycles from dicarbonyl compounds

: Various diketones such as 1,2-diketones, 1,3-diketones, 1,4-diketones, β-diketones and dicarbonyl compounds are used in the synthesis of core heterocyclic compounds such as pyrazoles, isoxazoles, triazoles and quinolones. They play an important role in synthetic organic chemistry. The diketones and dicarbonyl compounds also act as chelating ligands for the lanthanides and a large number of transition metals in material chemistry. 50% of drugs contain nitrogen heterocyclic compounds, so organic chemists have made efforts for the synthesis of nitrogen-containing heterocyclic compounds. This review article has compiled different methodologies for the synthesis of five- and six-membered nitrogen-containing heterocyclic compounds.

Efficient Regioselective Synthesis of Novel Condensed Sulfur–Nitrogen Heterocyclic Compounds Based on Annulation Reactions of 2-Quinolinesulfenyl Halides with Alkenes and Cycloalkenes

The preparation of novel reagents 2-quinolinesulfenyl chloride and bromide based on available 2-mercaptoquinoline has been described. This approach opens up opportunities for the introduction of 2-quinolinesulfenyl chloride and bromide into organic synthesis. Regioselective synthesis of novel 1,2-dihydro[1,3]thiazolo[3,2-a]quinolin-10-ium derivatives in high yields has been developed by annulation reactions of 2-quinolinesulfenyl chloride and bromide with alkenes. Condensed tetracyclic products have been obtained by the reactions of 2-quinolinesulfenyl chloride and bromide with cycloalkenes. The opposite regiochemistry in the reactions with styrene, isoeugenol and 1-alkenes was discussed.

Overview of chemistry and therapeutic potential of non-nitrogen heterocyclics as anticonvulsant agents

: Epilepsy is a chronic neurological disorder, characterized by predisposition of unprovoked seizures affecting the neurobiological, psychological, cognitive, economic, and social well-being of patient. As per the 2019 report by World Health Organization, it affects nearly 80% of the population which comes from the middle to low-income countries. It has been suggested that 70% of such cases can be treated effectively if properly diagnosed. It is one of the most common neurological diseases affecting 50 million people globally. Most of the antiepileptic drugs used in clinical practice are only 60-80% effective in controlling the disease. These drugs suffer from serious drawbacks of non-selectivity and toxicity that limit their clinical usefulness. Hence, there is a need to search for the safe, potent, and effective anti-epileptic drugs. One of the emerging strategies to discover and develop selective and non-toxic anticonvulsant molecule focuses on design of non-nitrogen heterocyclic compounds (NNHC). Drugs such as valproic acid, gabapentin, viagabatrin, fluorofelbamate, tiagabine, progabide, pregabalin, gamma amino butyric acid (GABA) etc., do not contain a nitrogen heterocyclic ring but are as effective anticonvulsants as conventional heterocyclic nitrogen compounds. This review covers the various classes of NNHC which have been developed in the recent past as anticonvulsants along with their chemistry, percentage yield, structure activity relationship and biological activity. The most potent compound in each series has been identified for the comparative studies, for further structural modification and to improve the pharmacokinetic profile. Various optimized synthetic pathways and diverse functionalities other than nitrogen-containing rings discussed in the article may help medicinal chemists to design safe and effective anticonvulsant drugs in near future.

Isoquinolone Syntheses by Annulation Protocols

Isoquinolones (isoquinolin-1(2H)-ones) are one of the important nitrogen-heterocyclic compounds having versatile biological and physiological activities, and their synthetic methods have been recently developed greatly. This short review illustrates the significant advances in the construction of isoquinolone ring with atom- and step-economy, focusing on the intermolecular annulation protocols and intramolecular cyclization in the presence of a variety of catalyst systems. The syntheses of isoquinolone-fused rings are also included.