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![Reusability of [HDBU][HSO4]](profile/Siddiqui-Madiha-Masroor/publication/357688752/figure/fig5/AS:11431281119420033@1676085932047/Reusability-of-HDBUHSO4_Q320.jpg)
A simple and efficient protocol has been developed for the synthesis of new1,2,3-triazole-2,3-dihydroquinazolin-4[1H]-one (DHQ) conjugates(6a−j) via ultrasound-assisted, solvent-free ionic liquid [HDBU][HSO4]-catalyzed reaction in good to excellent yields. This non-conventional, ultrasound-assisted route has taken the reactions over the conventiona...
Citations
... Table 5 lists the test solution's zone of inhibition. The results in Table 6 list some of the prepared derivatives 5-12 abilities to donate hydrogen or scavenge radicals utilizing the stable radical DPPH [40]. Figure 1 demonstrates that compound 1 and 2 present the donating group (NH 2 , NH, and SH), which can behave as agents of free radicals and are capable of opposing oxidation, and exhibit the highest antioxidant activity on DPPH, whereas the other compounds exhibit moderate activity because we observed the presence of electron withdrawing groups, such as Br, and the phenyl ring exhibited the lowest antioxidant activity [24]. ...
Several heterocyclic compounds bearing an imidazo(1,2a)pyridine moiety have been synthesized in this work, including triazole, thiazol, and thiazolone. This was done by condensation of 2-aminopyridine with 2-aminopyridine with 4-bromophencyl bromide or 4-phenylphencyl bromide to produce 2-substituted phenyl imidazo(1,2a)pyridine compounds 1 and 2. The Vilsmeier-Haak reaction was used to create the aldehyde group at position 3 of the 2-substituted phenyl imidazo(1,2a)pyridine ring (3 and 4). The reaction of compounds 3 and 4 with thiosemicarbazide afforded thiosemicarbazone derivatives 5 and 6 in 66 and 70% yields, respectively. These derivatives (5 and 6) were then subjected to three different cyclization reactions to obtain 1,3-thiazolone (7 and 8), 1,2,4-triazole (9 and 10), and 1,3-thiazole (11 and 12) derivatives. The FT-IR spectroscopy was used to confirm the structure of these derivatives, and the 1H NMR spectroscopy was used for some of them. A few of the produced compounds were examined for antimicrobial and antioxidant activities
... Although synthetically derived those compounds containing 1,2,3-triazole group have various biological activities such as anticancer [41][42][43][44] , antibacterial [45,46] , antifungal [47,48] , anti-HIV [49,50] , antituberculosis [51,52] , antioxidant [53,54] , antiproliferative [55,56] and enzyme inhibitory [57,58] , these compounds are not found in nature. Therefore, the importance of these compounds in medicinal chemistry field has become undeniable, and so 1,2,3-triazole groups have been described as a "pharmacophore group" with the meaning of the main functional group responsible for the effect of a drug compound and the synthesis of the related compound has been carried out by many scientists after that time [59] . ...
Click chemistry is totally an approach consisting of efficient and reliable reactions that bind two molecular building blocks and require no complex purification techniques. The aspire of achieving molecules with the desired characteristics and behaviour is the key to the click chemistry concept. In this concept, in order to obtain 1,2,3-triazole products as diversely functionalized molecules, copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has been widely used for years in the field of materials science, organic synthesis and the biochemistry. This review focusses on the importance of click chemistry for obtaining biologically active triazole molecules and therefore the applications of such 1,2,3-triazole derivatives in medicinal chemistry field are highlighted.
... 25 In view of the reported biological importance of guanidine, 26-28 1,2,3-triazole, specially, fully decorated 1,2,3-triazoles, [29][30][31] we speculated that molecular hybridization of both the scaffolds would result in better biological activity ( Figure 4). In continuation to earlier work on the triazole heterocyclic moiety [32][33][34][35][36][37][38][39][40] in this study, we report the synthesis of novel guanidine derivatives of 1,2,3-triazole as anti-inflammatory agents with potential antioxidant activity. The mechanism of inhibition of inflammation is studied via in silico study of docking interactions with COX-2 enzyme. ...
In search of new biologically potent molecules a small focused library of new guanidine-1,2,3-triazole hybrid derivatives were synthesized via Organocatalytic enolate- mediated azide-carbonyl [3 + 2] cycloaddition yielding a highly functionalized triazole core structure. The synthesis of all the derivatives were confirmed by spectral analysis ¹H NMR, ¹³C NMR and MS. The new guanidine-1,2,3-triazole conjugates were found to exhibit promising anti-inflammatory and antioxidant activity. The anti-inflammatory activity screened by membrane stabilization method summarizes the four potential conjugates 5c, 5f, 5h and 5g to be potent in comparison with standard drug Diclofenac sodium (DFS). The conjugates were also assessed for antioxidant potential by DPPH method. Among all the synthesized compounds, the compounds 5d, 5f, 5g and 5h exhibited potent antioxidant activity. Molecular docking study was performed to gain insight into the putative binding mode and binding strength of these compounds with the target enzyme Cyclo-oxygenase (COX-2) enzyme. The in vitro and in silico studies together with simpler designing and synthesis strategy via Organocatalytic enolate- mediated azide-carbonyl [3 + 2] cycloaddition followed by a two-component reaction with guanidine in basic conditions rationalize guanidine-1,2,3-triazole hybrid derivatives as easily assessable novel therapeutic agents.
... Although synthetically derived those compounds containing 1,2,3-triazole group have various biological activities such as anticancer [41][42][43][44] , antibacterial [45,46] , antifungal [47,48] , anti-HIV [49,50] , antituberculosis [51,52] , antioxidant [53,54] , antiproliferative [55,56] and enzyme inhibitory [57,58] , these compounds are not found in nature. Therefore, the importance of these compounds in medicinal chemistry field has become undeniable, and so 1,2,3-triazole groups have been described as a "pharmacophore group" with the meaning of the main functional group responsible for the effect of a drug compound and the synthesis of the related compound has been carried out by many scientists after that time [59] . ...
This paper demonstrated the preparation of flower-like TiO2 nanostructures by low temperature hydrothermal process from TiO2 nanoparticles. The as-synthesized TiO2 nanoparticles and flower-like TiO2 nanostructures were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and N2 adsorption-desorption measurements. The flower-like TiO2 nanostructures possessed good crystallinity, showed fairly large surface area of 220 m2/g and exhibited better photocatalytic degradation of rhodamine B than TiO2 nanoparticles under simulated solar radiation.
Introduction
Multicomponent reactions (MCRs) and green chemistry are essential criteria for the development of efficient chemical syntheses for valuable organic compounds.
Method
The design, synthesis, and development of sustainable procedures for the production of novel biological and pharmaceutical molecules have gained high importance. Herein, an environmentally benign synthesis of mono- and bis-2,3-dihydroquinazolin-4(1H)-ones as pharmaceutically active compounds was carried out in good to high yields of 80-99% within 45-120 minutes.
Result
The desired products were synthesized via three-component and pseudo five-component condensations of isatoic anhydride, a primary amine (aniline or ammonium acetate), and an aldehyde/dialdehyde using sulfamic acid (20%) as a solid acidic catalyst under the solvent-free condition at 100°C.
Conclusion
The easy work-up procedure, metal-free and environmentally benign catalyst, green reaction conditions for performing MCRs, and high yields of pure products are some advantages of the presented protocol.
Heterocycles have gained recognition as vital components in approved drugs, drawing substantial attention from the scientific community. Ionic liquids (ILs) have been utilized for their transformative roles in heterocycle synthesis, showcasing distinctive properties that are pivotal in diverse chemical transformations, while also acting as effective catalysts and offering safer alternatives to volatile organic solvents. This account delves into the synthesis of nitrogen- and oxygen-containing heterocyclic structures, employing various ILs such as ammonium, cholinium, DABCO-based, DBU-based, guanidinium-based, imidazolium, phosphonium, pyridinium, and other miscellaneous examples. They have proven indispensable in facilitating reactions like the Fischer indole synthesis, the Biginelli reaction, Knoevenagel condensations and many more. Notably, the recyclability of ILs serves as a valuable asset, aiding in the completion of intricate synthetic pathways, multicomponent reactions, and one-pot syntheses, ultimately enhancing yields. This account, covering the literature published in 2022, seeks to guide researchers in selecting suitable ILs for specific chemical reactions that enable the synthesis of aza- and/or oxa-heterocycles. The described advancements represent promising prospects for drug development and other applications within the domain of heterocyclic chemistry.
1 Introduction
2 Construction of Heterocycles Catalyzed by Ionic Liquids
2.1 Ammonium Ionic Liquids
2.2 Cholinium-Based Ionic Liquids
2.3 DABCO-Based Ionic Liquids
2.4 DBU-Based Ionic Liquids
2.5 Guanidinium-Based Ionic Liquids
2.6 Imidazolium Ionic Liquids
2.7 Phosphonium Ionic Liquids
2.8 Pyridinium Ionic Liquids
2.9 Other Ionic Liquids
3 Summary and Outlook
4 Abbreviations
