1,2,3-Triazole- and Quinoline-Based Hybrids with Potent Antiplasmodial Activity

Synthesis, crystal structure, Hirshfeld surface analysis, and DFT calculation of 4-(5-(((1-(3,4,5-trimethoxyphenyl)-1H-1,2,3-triazol-4-yl)methyl)thio)-4-phenyl-4H-1,2,4-triazol-3-yl)pyridine

Triazole is considered as a privileged scaffold in medicinal chemistry by virtue of it is diverse biological activity. several drugs currently in the market possess triazole moiety. In this study click chemistry was performed on the pyridine based 1,2,4-triazole-tethered propargyl moiety to afford 4-(5-(((1-(3,4,5-trimethoxyphenyl)-1H-1,2,3-triazol-4-yl)methyl)thio)-4-phenyl-4H-1,2,4-triazol-3-yl)pyridine. The new compound was fully characterized by 1H NMR, 13C NMR, HRMS and X-ray diffraction (XRD). XRD data indicated that, the structure shows: triclinic, space group P -1, a = 6.4427(3) A, ° b = 11.4352(4) A, ° c = 15.4510(5) A, ° α = 97.980(2)°, β = 96.043(2)°, γ = 92.772(2)°, V = 1118.75(7) Å 3, Z = 2, T = 152(2) K, μ(MoKα) = 0.094 mm-1, Dcalc = 1.364 g/cm3. Density functional theory (DFT) method along with Hirshfeld analysis of the optimized X-ray structure of the final product were used to confirm the molecular and the electronic structure of the reported compound.

Comprehensive Review on the Synthesis of [1,2,3]Triazolo[1,5-a]Quinolines

This report outlines the evolution and recent progress about the different protocols to synthesize the N-heterocycles fused hybrids, specifically [1,2,3]triazolo[1,5-a]quinoline. This review encompasses a broad range of approaches, describing several reactions for obtaining this since, such as dehydrogenative cyclization, oxidative N-N coupling, Dieckmann condensation, intramolecular Heck, (3+2)-cycloaddition, Ullman-type coupling and direct intramolecular arylation reactions. We divided this review in three section based in the starting materials to synthesize the target [1,2,3]triazolo[1,5-a]quinolines. Starting materials containing quinoline or triazole units previously formed, as well as starting materials which both quinoline and triazole units are formed in situ. Different methods of obtaining are described, such as metal-free or catalyzed conditions, azide-free, using conventional heating or alternative energy sources, such as electrochemical and photochemical methods. Mechanistic insights underlying the reported reactions were also described in this comprehensive review.

Antibacterial activity of the structurally novel C-2 amine-substituted analogues based on quinoxaline

In the current study, we have designed and prepared a series of quinoxaline-based compounds, which were derived from o-phenylenediamine. Among them, compounds 5m-5p displayed good to moderate antibacterial activity with MICs of 4-16 μg mL-1 against S. aureus, 8-32 μg mL-1 against B. subtilis, 8-32 μg mL-1 against MRSA and 4-32 μg mL-1 against E. coli, respectively. Compound 5p, identified as a potent broad-spectrum antibacterial agent, demonstrated the strongest inhibitory effects against a range of bacterial strains and low cytotoxicity, thereby warranting further investigation. Compound 5p not only demonstrated the ability to disperse established bacterial biofilms but also induced a slower development of bacterial resistance compared to norfloxacin. Moreover, bactericidal time-kill kinetic studies revealed that at a high concentration of 3MIC, compound 5p was capable of directly killing MRSA cells. The subsequent postcontact effect (PCE) results showed that the growth rate of viable bacteria (MRSA) was greatly impacted and did not recover in less than 24 hours, even after antibacterial agent 5p was removed. The drug-like properties and ADME prediction exhibited that 5m-5p obeyed Lipinski's rule of five and therefore presumably maintained moderate to good bioavailability and human intestinal absorption rate when administered orally. Mechanistic investigations have elucidated that compound 5p exerted its antibacterial effect by compromising the structural integrity of bacterial cell membranes, resulting in the leakage of intracellular constituents and ultimately causing bacterial demise. Further studies in vivo have demonstrated that 5p exhibited potent antibacterial efficacy against MRSA in murine corneal infection models, particularly at elevated concentrations. The current dataset has also been meticulously analyzed to delineate the structure-activity relationships (SARs) of the synthesized compounds.

Synthesis and evaluation of photophysical, electrochemical, and ROS generation properties of new chalcogen-naphthoquinones-1,2,3-triazole hybrids

This study presents a comprehensive analysis encompassing the synthesis, structural elucidation, photophysical behavior, and electrochemical properties of a novel series of chalcogen-naphthoquinone-1,2,3-triazole hybrids. Employing a meticulously designed protocol, the synthesis of these hybrids, denoted as 11a-j, was achieved with remarkable efficiency (yielding up to 81%). This synthesis used a regioselective copper-catalyzed azide-alkyne cycloaddition reaction (CuAAC). Furthermore, a detailed investigation into the photophysical characteristics, TDDFT calculations, electrochemical profiles, and photobiological attributes of compounds 11a-j was conducted. This exploration aimed to unravel insights into the excited state behaviors of these molecules, as well as their redox properties. Such insights are crucial for future applications of these derivatives in diverse biological assays.

Current development of 1,2,3-triazole derived potential antimalarial scaffolds: Structure- activity relationship (SAR) and bioactive compounds

Malaria is among one of the most devastating and deadliest parasitic disease in the world claiming millions of lives every year around the globe. It is a mosquito-borne infectious disease caused by various species of the parasitic protozoan of the genus Plasmodium. The indiscriminate exploitation of the clinically used antimalarial drugs led to the development of various drug-resistant and multidrug-resistant strains of plasmodium which severely reduces the therapeutic effectiveness of most frontline medicines. Therefore, there is urgent need to develop novel structural classes of antimalarial agents acting with unique mechanism of action(s). In this context, design and development of hybrid molecules containing pharmacophoric features of different lead molecules in a single entity represents a unique strategy for the development of next-generation antimalarial drugs. Research efforts by the scientific community over the past few years has led to the identification and development of several heterocyclic small molecules as antimalarial agents with high potency, less toxicity and desired efficacy. Triazole derivatives have become indispensable units in the medicinal chemistry due to their diverse spectrum of biological profiles and many triazole based hybrids and conjugates have demonstrated potential in vitro and in vivo antimalarial activities. The manuscript compiled recent developments in the medicinal chemistry of triazole based small heterocyclic molecules as antimalarial agents and discusses various reported biologically active compounds to lay the groundwork for the rationale design and discovery of triazole based antimalarial compounds. The article emphasised on biological activities, structure activity relationships, and molecular docking studies of various triazole based hybrids with heterocycles such as quinoline, artemisinins, naphthyl, naphthoquinone, etc. as potential antimalarial agents which could act on the dual stage and multi stage of the parasitic life cycle.

Recent developments in antimalarial activities of 4-aminoquinoline derivatives

Malaria is the fifth most lethal parasitic infection in the world. Antimalarial medications have played a crucial role in preventing and eradicating malaria. Numerous heterocyclic moieties have been incorporated into the creation of effective antimalarial drugs. The 4-aminoquinoline moiety is favoured in antimalarial drug discovery due to the diverse biological applications of its derivative. Since the 1960s, 4-aminoquinoline has been an important antimalarial drug due to its low toxicity, high tolerability, and rapid absorption after administration. This review focused on the antimalarial efficacy of the 4-aminoquinoline moiety hybridised with various heterocyclic scaffolds developed by scientists since 2018 against diverse Plasmodium clones. It could aid in the future development of more effective antimalarial agents.

Synthesis, antimicrobial, antibiofilm and computational studies of isatin-semicarbazone tethered 1,2,3-triazoles

In present era, heterocyclic compounds containing two or three nitrogen atoms play a vital role in drug discovery. In this context, a new class of isatin-semicarbazone tethered 1,2,3-triazole hybrids was synthesized via Cu(I)-mediated azide alkyne cycloaddition reaction. Structural characteristics of the newly derived compounds were identified by various spectral techniques like FTIR, ¹H NMR, ¹³C NMR, HRMS and single crystal X-ray crystallography. Synthesized derivatives were also screened for in vitro antimicrobial and antibiofilm activity against different microbial species. Triazole hybrid 7e showed significant efficacy towards E. coli having MIC of 0.0063 µmol/mL, whereas 6a, 6b, 7a, 7c, 7e, and 7f showed highest percentage of biofilm inhibition against P. aeruginosa. Bioassay results suggested that these triazole hybrids could act as biomaterial for antimicrobial and antibiofilm applications and may constitute a new promising class of antimicrobial and antibiofilm agents. These results were further supported by in silico docking, DFT calculations and ADME studies.

Cyanoacetohydrazide linked to 1,2,3-triazole derivatives: a new class of α-glucosidase inhibitors

In this work, a novel series of cyanoacetohydrazide linked to 1,2,3-triazoles (9a–n) were designed and synthesized to be evaluated for their anti-α-glucosidase activity, focusing on the fact that α-glucosidase inhibitors have played a significant role in the management of type 2 diabetes mellitus. All synthesized compounds except 9a exhibited excellent inhibitory potential, with IC50 values ranging from 1.00 ± 0.01 to 271.17 ± 0.30 μM when compared to the standard drug acarbose (IC50 = 754.1 ± 0.5 μM). The kinetic binding study indicated that the most active derivatives 9b (IC50 = 1.50 ± 0.01 μM) and 9e (IC50 = 1.00 ± 0.01 μM) behaved as the uncompetitive inhibitors of α-glucosidase with Ki = 0.43 and 0.24 μM, respectively. Moreover, fluorescence measurements were conducted to show conformational changes of the enzyme after binding of the most potent inhibitor (9e). Calculation of standard enthalpy (ΔHm°) and entropy (ΔSm°) values confirmed the construction of hydrophobic interactions between 9e and the enzyme. Also, docking studies indicated desired interactions with important residues of the enzyme which rationalized the in vitro results.