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Natural products are a boundless source for the development of pharmaceutical agents against a wide range of human diseases. Accordingly, naturally occurring aurones possess various biological benefits, such as anticancer, antioxidant, antimicrobial, antidiabetic, anti-inflammatory, antiviral and neuroprotective effects. In addition, various studies have revealed that aurones are potential templates for the regulation of diabetes mellitus and its associated complications. Likewise, certain aurones and their analogues have been found to be remarkable kinase inhibitors of DARK2, PPAR-γ, PTPM1, AGE, α-amylase and α-glucosidase, which represents a promising approach for the treatment of chronic metabolic disorders such as diabetes. Therefore, in our present study, we provide a detailed account of the advances in aurones as antidiabetic agents over the past decade.

Polyureas (PUs) have already found wide practical applications, and various methods of their synthesis have been reported. In this manuscript, we wished to report the very first mechanochemical approach towards aromatic PUs via reactions between isomeric 2,2′-, 3,3′-, and 4,4′-diaminobiphenyls and triphosgene under solvent-free conditions following ball-milling. By using this synthetic approach, both PUs and azomethine-capped Pus were obtained. The fluorescence response of the above-mentioned PUs towards various anions in solutions were studied and selective fluorescence responses towards the hydroxyl and fluoride anions were observed.

Two new azaheterocycle-based bolas, such as (1-(4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl)-1H-1,2,3-triazol-4-yl)-methylenyls α,ω-bisfunctionalized PEGs, were prepared via Cu-catalyzed click reaction between 2-(4-azidophenyl)-5-(aryl)-oxadiazole-1,3,4 and terminal ethynyls derived from PEG-3 and PEG-4. Due to the presence of two heteroaromatic cores and a PEG linker, these bola molecules are considered as promising fluorescent chemosensors for electron-deficient species. As a result of a well-pronounced “turn-off” fluorescence response towards common nitro-explosive components, such as 2,4-dinitrotoluene (DNT) and 2,4,6-trinitrotoluene (TNT), hard-to-detect pentaerythritol tetranitrate (PETN), as well as Hg2+ cation was observed.

A solvent‐free reaction between C6‐unsubstituted 5‐aryl‐1,2,4‐triazines and 2‐amino‐4‐aryloxazoles at high temperature was studied. The reaction proceeds via inverse electron demand aza‐Diels‐Alder reaction between the oxazole moiety as dienophile and the 1,2,4‐triazine moiety as diene with the highly regioselective formation of 3,6‐diarylpyridines in up to 60 % isolated yield. The structure of one of the key‐products was proven by the X‐ray diffraction analysis, and the mechanism of the transformation was proposed. The reaction proceeds well for both 6‐aryl and 6‐hetaryl‐1,2,4‐triazines in the presence of the electron acceptor substituent at the position 3. In the case of the donor substituent in position 3, the pyridine yields are significantly reduced. In the case of 5,6‐nonsubstituted 1,2,4‐triazines, the triazine cycle is degraded without product formation. The high regioselectivity of the reaction as well as solvent‐free conditions are valuable advantages of the present synthetic approach. [ABSTRACT FROM AUTHOR]

The privileged 1,2,3‐triazole scaffold is drawing researcher's attention due to its widespread applications in diverse fields such as drug discovery (e.g., carboxyamidotriazole), organic synthesis (click‐reaction template), polymeric materials (e.g., triazolamer), supramolecular receptors (e.g., triazolophane), fluorescent materials (e.g., metal–organic frameworks), and agricultural sectors (e.g., fungicides). Various 1,2,3‐triazole persuasion modules are also currently available in the market that have multiple assets such as active pharmaceuticals and agricultural purposes. Owed to the highly consistent and firmest synthesis approach, that is, click reaction of various azides and acetylene derivatives by copper (I)‐catalyzed 1,3‐dipolar cycloaddition (CuAAC), highly functionalized 1,2,3‐triazoles are prepared in scalar yields for drug discovery. Given the importance of 1,2,3‐triazole chemistry, the present review focuses specifically on the synthesis of structurally diverse 1,2,3‐triazoles linked to natural pharmacophores and their biological importance. Furthermore, the dual/multi‐pharmacophores assimilated 1,2,3‐triazoles have listed interesting biological activities that could be valuable as future drug leads. In addition, this comprehensive review can serve as a template for the development of new diverse scaffolds that will ensure for new therapeutic approaches for the existing myriad diseases and disorders. [ABSTRACT FROM AUTHOR]

Nucleotide analogues are the divergent scaffolds that are reliable potential therapeutic drugs to treat the wide range of diseases including viral infections. For instance, Remdesivir is a biologically important nucleotide analogue prodrug that can act as a key drug target for the diseases Ebola and COVID-19. Remdesivir is a structurally chiral aryloxy-phosphoramidate prodrug as it is metabolized into nucleoside triphosphate (active drug form) inside the cell through sequential reactions by ester mediated-hydrolysis. Thus, the current minireview focuses on the earlier reported synthetic approaches of key fragments of remdesivir and their developments to attain the scale-up yields of the drug for clinical/commercial applies. Further, this review serves as a template for the design and development of other complex organic molecules. [ABSTRACT FROM AUTHOR]

An operationally facile and high yielding one‐pot protocol has been developed for the preparation of pyridines appended with pyrazole via NH linker. This protocol includes SNipso/aza‐Diels‐Alder reactions in up to 54 % yields starting from 1,2,4‐triazine precursors. All the synthesized compounds have been evaluated for their in silico activity against JAK1, SYK, and FAK1 kinases. The most promising compound was tested in vitro using A‐172, Hs578T, and HepG2 cancer cell lines and exhibited considerable cytotoxicity with IC50 values <50 μM in A‐172 and HepG2 cell lines. Anticancer in vitro activity correlates well with the predicted in silico data. [ABSTRACT FROM AUTHOR]

The present study describes a facile and solvent free synthesis of 1,2,4-triazine antipyrine derivatives (2a–f) in prominent yields (70–85%) over nucleophilic substitution of 5-carbonitrile triazines. Further, we strained to convert them into pyridine analogues (3a–f) over aza-Diels-Alder reaction with norbornadiene as dienophile but it was an unsuccessful attempt. It is an assumption we made that the antipyrine substituent primes the triazine electronically unfavorable at 1,2-aza position. All the synthesized compounds were confirmed by using 1H NMR, 19F NMR, 13C NMR and Mass spectral studies. Furthermore, this stated synthetic approach is ecofriendly as there are no toxic intermediates and also, the antipyrine derivatives can be aiding as promising templates for the development of new pharmaceutical scaffolds. [ABSTRACT FROM AUTHOR]

A convergent and efficient approach towards the total synthesis of Kadcotrione B is described. For this purpose, the syntheses of two fragments, 6/6/5-fused tricyclic ring and C-9 side chain, were accomplished. The salient features of these syntheses are the utilization of aldol condensation, Evans aldol reaction, Horner–Wadsworth–Emmons olefination, Michael addition, Robinson annulation, and Wacker oxidation. [ABSTRACT FROM AUTHOR]

A series of N‐substituted maleimide derivatives have been developed via acetic acid‐mediated microwave reaction pathway, which was identified as the incomparable method for this maleimide compounds. All the synthesized compounds were tested for antioxidant activity by DPPH and H2O2 methods. Compounds 5h and 5m were displayed with higher antioxidant activity in two methods. The structure–activity relationship demonstrated that the compounds having electron releasing substitutions 5h and 5m generally show beneficial activity than electron capture substitution cores. Thus, compounds 5h and 5m may be useful as an exogenous antioxidant. [ABSTRACT FROM AUTHOR]