Mini-Reviews in Organic Chemistry - Volume 17, Issue 8, 2020

1, 3, 5-Triazine (s-Triazine) is a versatile nucleus to design and develop potent bioactive molecules for drug discovery, particularly in cancer therapy. The aim of this review is to present the most recent trends in the field of synthetic strategies made for functionalized triazine derivatives active against cell proliferation. This review article covers the synthesis of aryl methylamino, morpholino, triamino substituted triazines, antimitotic agents coupled triazines and many more. Many 1,3,5- triazine derivatives, both hetero-fused and uncondensed, have shown remarkable antitumor activities. We have highlighted various derivatives with 1, 3, 5-triazine core targeting different kinases with an aim to help researchers for developing new 1, 3, 5-triazine derived compounds for antitumor activity.

The chemistry of hypervalent iodine compounds has been experiencing considerable attention of organic chemists during the past few years. Hypervalent iodine reagents have found ubiquitous applications in organic synthesis because of their mild and highly chemoselective oxidizing properties, easy commercial availability, and environmental benign character. Along with oxidation of alcohol, they have also shown to be useful in number of organic transformations which include oxidative functionalization of carbonyl compounds, catalytic imidations, cyclization, oxidative coupling of phenols, amines and related compounds. Among various hypervalent iodine reagents, iodine-V compounds (λ5-iodanes) have attracted much attention in recent years. This review narrates the particular advances in iodine (V) reagents with special emphasis on the use of DMP in organic transformations.

2,4-Thiazolidinediones are versatile scaffolds with a unique structural feature of hydrogen bonding donor and the hydrogen bonding acceptor region. This review deals with the synthesis of various bio-active 2,4-thiazolidinedione derivatives. It is presented on the basis of the linker variations at 3^rd & 5^th positions of 2,4-thizolidinediones. Biological evaluations of various derivatives thus prepared and toxicity studies on the respective products as given by various researchers/ Research groups have been described.

The design of the environmentally friendly approach to the synthesis of biologically important compounds without compromising the yield has been the focus of many chemists in recent years. The development of the one-pot synthesis of heterocycles in the presence of Ionic Liquids (ILs), used as both environmental media and catalysts, is efficient and environmentally sustainable. This review highlights the one-pot synthesis of imidazoles in acidic ILs in the past decade. Some reviews have been conducted on imidazoles, such as their pharmacological importance. Hence, we decided to focus on their synthesis in acidic ionic liquids, which the authors are not aware of any published literature.

Triazine, one of the nitrogen containing heterocyclic compounds has attracted the considerable interest of researchers due to the vast array of biological properties such as anti-viral, antitumor, anti-convulsant, analgesic, antioxidant, anti-depressant, herbicidal, insecticidal, fungicidal, antibacterial and anti-inflammatory activities offered by it. Various antibacterial agents have been synthesized by researchers to curb bacterial diseases but due to rapid development in drug resistance, tolerance and side effects, there had always been a need for the synthesis of a new class of antibacterial agents that would exhibit improved pharmacological action. Therefore, this review mainly focuses on the various methods for the synthesis of triazine derivatives and their antibacterial activity.

The benzimidazole moiety, being a versatile heterocyclic unit, finds potential utility in multiple applications ranging from material science to medicinal chemistry. Benzimidazole derivatives are widely chosen as a multifunctional unit for the synthesis of bioactive organic compounds because of their structural similarities to the natural nucleotides. They are also used as heteroaromatic scaffolds in molecular probes for sensing and bio-imaging. Amphoteric nature of the benzimidazole ring forms the basis of designing new fluorescent architectures for various metal ions, anions, nitroaromatics as well as neutral organic molecules. Alongside, recent years have also witnessed the emerging development of benzimidazole-based supramolecular gels, useful in sensing and water purification. Supramolecular gels are a special class of self-assembled structures formed by weak noncovalent interactions between the molecules and are easily tuned by external stimuli. Such stimuliresponsive gels serve as smart materials because of their abilities to undergo gel-to-gel, or gel-to-sol transition upon subtle change of the gel environment. Of various stimuli, ion coordination draws attention for their visual detection and to adapt material properties. The ion-sensitive gels act as fascinating biomaterials with potential applications in drug delivery, optoelectronics and catalysis. Thus, designing of such ion-responsive gels is challenging. The rising popularity of benzimidazole based-gels is related to its advanced properties such as π-bridging, hydrogen bonding, fluorescence and ion coordinating abilities. This review focuses on recently developed various ion-responsive benzimidazole motif-based supramolecular gelators by summarising the crucial role of the structural parameters of benzimidazole gelators. Beside ion sensing, we also desire to summarize other possible applications of gelators in material chemistry. Finally, the necessity and possibility of further exploration of benzimidazole/ benzimidazolium derived gelators are briefly described.