Aromatic Azides Research Articles

Synthesis and Anticancer Evaluation of Tryptanthrin‐1,2,3‐Triazole Hybrids

ABSTRACTSynthesis of 18 tryptanthrin‐triazole hybrid molecules by employing Cu(I)‐catalyzed azide‐alkyne [3 + 2] cycloaddition (CuAAC) between tryptanthrin oxime O‐propargyl ether and aromatic azides is described here. The exclusive formation of E‐triazoles was confirmed by theoretical studies using the M06‐2x/6–311++G(d,p) level. From the synthesized triazoles, four of them have been selected and were subjected to in vitro anticancer activity studies against selected cell lines. Furthermore, in silico studies have been conducted for the most active compound, 5h, and it suggested that various noncovalent interactions and one conventional hydrogen bond enhance the stability of the complex (binding affinity = −11.29 kcal/mol). ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) studies also prove the increased biological potency of 5h.

Synthesis of 4-(3-(1-substituted/unsubstituted-phenyl-1H-1,2,3-triazole-4-yl)propoxy)benzaldehydes: In vitro antimicrobial, antimalarial activities and In silico docking study

In this work, we have developed new derivatives of 4-(3-(1-substituted/unsubstituted phenyl-1H-1,2,3-triazol-4-yl)propoxy)benzaldehydes 3(a-o) in good to excellent yield through the click reaction catalyzed by Copper(II) sulfate pentahydrate. 5-chloropent-1‑yne was used as an alkynylation reagent for 4-hydroxybenzaldehyde, whereas the aromatic azides were prepared from the corresponding diazonium salt by diazotization. All the newly synthesized derivatives were well characterized by FT-IR, 1H/ 13C NMR, high-resolution mass spectrometry and elemental analyses. These compounds were evaluated for their in vitro anti-microbial against six pathogenic strains as well as two pathogenic strains as anti-fungal activities using the broth dilution method. The activity results show that most of the compounds exhibit moderate to very good antibacterial and antifungal activities compared to the reference drugs. Furthermore, the in vitro antimalarial assay of synthesized compounds was screened against P. falciparum strain and then compared to Quinine and Chloroquine as the reference drugs. The results from the activity evaluation revealed that three out of fifteen compounds presented moderate efficacy when compared to Quinine. The structure-activity relationship (SAR) study indicated that substituted compounds with deactivating groups have potent antibacterial, antifungal, and antimalarial activities. Moreover, in silico molecular docking assay shows that 3 m is the most potent amongst 3(a-o) with a binding energy of -8.1 kcal/mol and -8.9 kcal/mol in the binding pocket of the receptor for bacterial and fungal infections, respectively compared to the standard drugs. The molecule 3 m has been studied in details for its ADMET properties and showed the most promise as a drug candidate.

Efficient and Robust Dynamic Crosslinking for Compatibilizing Immiscible Mixed Plastics through In Situ Generated Singlet Nitrenes.

Creating a sustainable economy for plastics demands the exploration of new strategies for efficient management of mixed plastic waste. The inherent incompatibility of different plastics poses a major challenge in plastic mechanical recycling, resulting in phase-separated materials with inferior mechanical properties. Here, this study presents a robust and efficient dynamic crosslinking chemistry that effectively compatibilizes mixed plastics. Composed of aromatic sulfonyl azides, the dynamic crosslinker shows high thermal stability and generates singlet nitrene species in situ during solvent-free melt-extrusion, effectively promoting C─H insertion across diverse plastics. This new method demonstrates successful compatibilization of binary polymer blends and model mixed plastics, enhancing mechanical performance and improving phase morphology. It holds promise for managing mixed plastic waste, supporting a more sustainable lifecycle for plastics.

Copper Dispersed Covalent Organic Framework for Azide-Alkyne Cycloaddition and Fast Synthesis of Rufinamide in Water.

A crystalline porous bipyridine-based Bpy-COF with a high BET surface area (1864m2g-1) and uniform mesopore (4.0nm) is successfully synthesized from 1,3,5-tris-(4'-formyl-biphenyl-4-yl)triazine and 5,5'-diamino-2,2'-bipyridine via a solvothermal method. After Cu(I)-loading, the resultant Cu(I)-Bpy-COF remained the ordered porous structure with evenly distributed Cu(I) ions at a single-atom level. Using Cu(I)-Bpy-COF as a heterogeneous catalyst, high conversions for cycloaddition reactions are achieved within a short time (40min) at 25°C in water medium. Moreover, Cu(I)-Bpy-COF proves to be applicable for aromatic and aliphatic azides and alkynes bearing various substituents such as ester, hydroxyl, amido, pyridyl, thienyl, bulky triphenylamine, fluorine, and trifluoromethyl groups. The high conversions remain almost constant after five cycles. Additionally, the antiepileptic drug (rufinamide) is successfully prepared by a simple one-step reaction using Cu(I)-Bpy-COF, proving its practical feasibility for pharmaceutical synthesis.

Synthesis of Novel Series of 1,2,3-Triazoles Tethered to Pyrazolo[3,4-d]pyrimidine Scaffold with Methoxyphenoxy Linker

A novel series of hybrid heterocycles having pyrazolopyrimidine based 1,2,3-triazole scaffold with two ether linkages were synthesized by 1,3-dipolar cycloaddition reaction of pyrazolopyrimidines tethered to phenoxy alkynes and differently substituted aromatic azides using CuSO4·5H2O and sodium ascorbate mixture as catalyst in DMSO-H2O solvent mixture. The synthesized triazole hybrids were characterized by using various spectroscopic techniques.

Photoinitiated Rearrangement of Aromatic Azides to 2-Aminonicotinates.

This study describes a one-pot photoinduced method for azepine synthesis and their subsequent rearrangement into pyridines. The rearrangement of the azepine, formed during photolysis, occurs due to both thermal and photochemical activation of the reaction. This requires an electron-donating substituent at the second position of the azepine and an electron-withdrawing substituent at the third position of the azepine. A reaction mechanism has been proposed to explain the role of water and the nature of the azepine substituents.

Click synthesis and self-assembly of novel dendritic ethylene glycol/alkyl-substituted diarylated triazoles into supramolecular nanofibers

Copper-catalyzed 1, 3-dipolar cycloaddition reaction between azides and alkynes under mild conditions has been known to exhibit high selectivity and good yields of 1, 2, 3-triazole. Additionally, 1, 2, 3-triazoles are used in various medical and pharmaceutical applications. Herein, we present novel low molecular weight organogelators from fluorescent ethylene glycol/alkyl-substituted 2, 6-diarylated pyridine 1, 2, 3-triazoles. Compact supramolecular architectures were created by the self-assembly of the synthesized gelators. The gel formation activity of the prepared ethylene glycol/alkyl-substituted 2, 6-diarylated pyridine triazoles were presented. The synthesis process was achieved by copper-catalyzed alkyne-azide cycloaddition (CuAAC) of ethylene glycol/alkyl-functionalized aromatic azide with aromatic alkyne bearing alkyl ester tails of various lengths. The ethylene glycol/alkyl-functionalized diaryl triazoles were investigated by 1H/13C NMR and FTIR spectroscopic methods. Triazoles with long ethylene glycol and/or alkyl ester tails showed an enhanced gelation activity as compared to those with shorter ethylene glycol and/or alkyl ester tails. The morphological features of the self-assembled ethylene glycol/alkyl-substituted arylated triazoles were studied by scanning electron microscopy (SEM), demonstrating supramolecular nanofibrous assemblies. Those supramolecular assemblies were forced by van der Waals and π-stacks interactions. Both antibacterial activity and cytotoxicity of the synthesized arylated triazole gelators were studied.

Design, Synthesis and Cytotoxicity of New Coumarin-1,2,3-triazole Derivatives: Evaluation of Anticancer Activity and Molecular Docking Studies.

A library of new coumarin-1,2,3-triazole hybrids 7a-l were synthesized from 4-(diethylamino)-2-hydroxybenzaldehyde precursor through a series of reactions including Vilsmeier-Haack reaction and condensation reaction to achieve key intermediate oxime and further performed click reaction by using different aromatic azides. We screened all molecules in silico against crystal structure of Serine/threonine-protein kinase 24 (MST3), based on these results all molecules were screened for their cytotoxicity against human breast cancer MCF-7 and lung cancer A-549 cell lines. Compound 7 b (p-bromo) showed best activity against both cell lines MCF-7 and A-549 with IC50 value of 29.32 and 21.03 μM, respectively, in comparison to Doxorubicin corresponding IC50 value of 28.76 and 20.82 μM. Another compound 7 f (o-methoxy) also indicated good activity against both cell lines with IC50 value of 29.26 and 22.41 μM. The toxicity of all compounds tested against normal HEK-293 cell lines have not shown any adverse effects.

Substituents role in highly symmetrical 1,2,3-triazoles derivatives toward self-assembly of soft liquid crystals

Triazole bent-core mesogens based on symmetrical bent-shaped of two 1,2,3-triazole ring arms were synthesized and characterized. The the thermail stability of those new synthesised mesogens from the embient temperature to 215 °C giving mesogenic phase transitions over a wide temperature range is investigated. A study of different substituents located on the rigid bentcore was carried out for compact supramolecular innovated architectures which were produced by self-assembly of many triazoles soft crystals with a liquid crystals behaviour. The synthetic procedures, characterizations and polymorphism of four novel bent-core mesogens comprising symmetrical 1,2,3-triazole arms were demonstrated. The preparation process was carried out through‘‘click chemistry’’ via Cu-catalyzed azide-alkyne cycloaddition of nitro- and alkyl-substituted aromatic azides with aromatic compounds, comprising terminal alkyne groups and long alkyl or alkoxy side-chains. The triazole derivatives were fully characterized by 1H/13C NMR, Fourier-transform infrared spectroscopy (FTIR) and elemental analysis. The mesophases and textures were examined by employing polarizing optical microscope (POM), differential scanning calorimetry (DSC) and X-ray Diffraction (XRD). The analogues with shorter alkoxy terminal substituents displayed higher mesomorphic properties with wide mesomorphic temperature ranges compared to analogues with shorter alkoxy terminals. The morphological characteristics of the self-assembled triazoles were investigated by scanning electron microscopy (SEM) which demonstrated arrangement of highly ordered columnar architectures. These orders were driven by layer to next layer adjacent influences and π-π stacking. The effect of 1,2,3-triazole ring and length of terminal aliphatic chains on the liquid crystalline performance were discussed. Through an appropriate choice of lateral structures employing “click chemistry’’, both transition temperature and mesophases ranging from isotropic to columnar or B1/B4-like supramolecular liquid crystalline aggregates can be tuned.

Discovery of New Boswellic Acid Hybrid 1H-1,2,3-Triazoles for Diabetic Management: In Vitro and In Silico Studies.

A series of 24 new 1H-1,2,3-triazole hybrids of 3-O-acetyl-11-keto-β-boswellic acid (β-AKBA (1)) and 11-keto-β-boswellic acid (β-KBA (2)) was designed and synthesized by employing "click" chemistry in a highly efficient manner. The 1,3-dipolar cycloaddition reaction between β-AKBA-propargyl ester intermediate 3 or β-KBA-propargyl ester intermediate 4 with substituted aromatic azides 5a-5k in the presence of copper iodide (CuI) and Hünig's base furnished the desired products-1H-1,2,3-triazole hybrids of β-AKBA (6a-6k) and β-KBA (7a-7k)-in high yields. All new synthesized compounds were characterized by 1H-, 13C-NMR spectroscopy, and HR-ESI-MS spectrometry. Furthermore, their α-glucosidase-inhibitory activity was evaluated in vitro. Interestingly, the results obtained from the α-glucosidase-inhibitory assay revealed that all the synthesized derivatives are highly potent inhibitors, with IC50 values ranging from 0.22 to 5.32 µM. Among all the compounds, 6f, 7h, 6j, 6h, 6g, 6c, 6k, 7g, and 7k exhibited exceptional inhibitory potency and were found to be several times more potent than the parent compounds 1 and 2, as well as standard acarbose. Kinetic studies of compounds 6g and 7h exhibited competitive and mixed types of inhibition, with ki values of 0.84 ± 0.007 and 1.18 ± 0.0012 µM, respectively. Molecular docking was carried out to investigate the binding modes of these compounds with α-glucosidase. The molecular docking interactions indicated that that all compounds are well fitted in the active site of α-glucosidase, where His280, Gln279, Asp215, His351, Arg442, and Arg315 mainly stabilize the binding of these compounds. The current study demonstrates the usefulness of incorporating a 1H-1,2,3-triazole moiety into the medicinally fascinating boswellic acids skeleton.

Synthesis, Anticancer and Antibacterial Activity of Mannose-based bis-1,2,3-Triazole Derivatives

In the current work, aromatic amines and alkyl halides have been converted to the corresponding azides 2a‒d and 4a-d by the reaction with sodium nitrite and sodium azide respectively for amines and sodium azide for halides. Then, dipropargyl ether derivative of D-mannose 8 has been synthesized from diacetone mannose that has been obtained by the treatment of D-mannose (5) with dry acetone in the presence of sulfuric acid. Then, aldol condensation has been used to prepare diol 7 from the mannose diacetonide 6. The reaction of compound 7 with propargyl bromide in alkaline media has been afforded dipropargyl derivative 8. In a parallel step, both dialkyne with aromatic and aliphatic azide have been coupled to produce 1,2,3-triazole derivatives 9a‒d in the presence of Cu(I) salts. All synthesized compounds have been characterized by 1D and 2D NMR spectra alongside with HRMS data. The antibacterial activity against both gram-positive and gram-negative has been tested. Moreover, the anticancer activity has also been evaluated against AMJ13 cell line.

Construction of Axial Chirality via Click Chemistry: Rh-Catalyzed Enantioselective Synthesis of 1-Triazolyl-2-Naphthylamines.

A modular and practical click chemistry for atroposelective synthesis of 1-triazolyl-2-naphthylamines is developed. In this protocol, a variety of aromatic or aliphatic azides, and 1-alkynyl-2-naphthylamines could be assembled into valuable 1-triazlyl-2-naphthylamine scaffolds via a [3 + 2] cycloaddition under Rh-catalysis. This asymmetric click technology features easily accessible starting materials, mild reaction conditions, facile scalability, and good enantioselectivity. The good thermostability of products showcases great applicable potential, and the synthetic transformations further expand the molecular diversity of atropisomers.

Hybrids of thiazolidinone with 1,2,3-triazole derivatives: design, synthesis, biological evaluation, in silico studies, molecular docking, molecular dynamics simulations, and ADMET profiling

A new series of thiazolidinone linked 1,2,3-triazole hybrids 5a-h was designed and synthesized using the copper-catalyzed Huisgen azide-alkyne cycloaddition (CuAAC) between thiazolidinone linked alkyne and aromatic azides. The structures of the newly synthesized compounds were established by NMR (1H and 13C) and HRMS. The targeted thiazolidinone-1,2,3-triazole hybrids were evaluated for their cytotoxic activity against four human cancer cell lines, including fibrosarcoma (HT-1080), lung carcinoma (A-549), and breast carcinoma (MCF-7 and MDA-MB-231) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliun bromide (MTT). The obtained data showed that most of these compounds have moderate anti-proliferative activity with IC50 values between 10.26 ± 0.71 and 53.93 ± 1.20 μM. The compound 5a exhibited higher activity with an IC50 value of 10.26 ± 0.71 µM, compared to 5d with an IC50 value of 11.56 ± 1.98 µM for the HT-1080 and MCF-7 cancer cells line, respectively. Moreover, Annexin-V apoptosis was assessed by flow cytometry for hybrid compounds 5a and 5d against HT-1080 and MCF-7 competitor cell lines, as they increase the level of active caspase 3/7. The experimental results were further confirmed by docking studies followed by molecular dynamic simulations. Both the potent derivatives i.e. 5a and 5d have comparable docking scores and MD simulations results showed that the docked complex of 5a is somewhat more stable than 5d primarily for protein p53. The ADMET profile of both derivatives established their safety zone and drug-like potential. Communicated by Ramaswamy H. Sarma

SYNTHESIS AND ANTICANCER EVALUATION OF NEW 1HNAPHTHO[2,3-D] IMIDAZOLE-4,9-DIONE-1,2,3 TRIAZOLE HYBRIDS

A new series of 1H-naphtho[2,3-d]imidazole-4,9-dione-based 1,2,3-triazole hybrids (10a-10n) were synthesized by the reaction of 1-(prop-2-yn-1-yl)-1H-naphtho[2,3-d]imidazole-4,9-dione with aromatic azides via copper-catalyzed azide-alkyne cycloaddition reactions. All the synthesized compounds are screened for their in vitro anticancer activities against three cancer cell lines namely MCF-7 (breast), HeLa (cervical), and A-549 (lung) using an MTT assay. The results revealed that the compounds 10a,10c,10g, and 10k exhibited promising activity against three cancer cell lines. Especially, compound 10a displayed higher activity against all the cell lines than the standard drug, The molecular docking studies of compounds 10a-10n as EGFR targeting agents were also supported by the observed IC50 data.

Cascade Cross‐Coupling/Spirocyclization/Formal [4+2] Cycloaddition Reactions of 3‐(2‐Isocyanoethyl)Indoles with Aromatic Azides: Access to Polycyclic Spiroindolines Bearing A Pentasubstituted Guanidine Moiety

AbstractA rhodium‐catalyzed cascade cross‐coupling/spirocyclization/formal [4+2] cycloaddition reaction of 3‐(2‐isocyanoethyl)indoles with aromatic azides is developed, providing a general synthetic protocol to polycyclic spiroindolines bearing a pentasubstituted guanidine moiety with moderate to excellent yields. This transformation is highly effective since one C−C, one C=N, three C−N bonds as well as two new rings are constructed in a single step. More importantly, this work represents a new reactivity pattern of 3‐(2‐isocyanoethyl)indole, and thus constitutes an valuable addition to 3‐(2‐isocyanoethyl)indole chemistry.magnified image

Phthalimide/Naphthalimide containing 1,2,3-triazole hybrids: Synthesis and Antimicrobial Evaluation

A series of twenty-eight Phthalimide/Naphthalimide containing 1,2,3-triazole hybrids (6a-6z2) have been synthesized based on hybrid pharmacophore concept through Click reaction of terminal alkynes (3a-3d) with aromatic azides (5a-5 g). All the synthesized Phthalimide/Naphthalimide containing 1,2,3-triazole hybrids were characterized utilizing various spectral techniques like 1D, 2D NMR, FTIR and HRMS. Further, the structure of synthesized compound 6b (CCDC 2,192,005) was also confirmed by Single Crystal X-ray Crystallography. Additionally, In vitro antimicrobial activity of the synthesized hybrids were performed against two Gram positive bacterial strains and two Gram negative bacterial strains as well as two parasitic strains by serial dilution technique. The compound 6e (MIC 0.0179 µmol/mL) demonstrated excellent antimicrobial potency due to presence of nitro group on phenyl ring against all tested strains. The binding conformation of the most potent Phthalimide/Naphthalimide containing 1,2,3-triazole hybrid 6e with E. coli topoisomerase II DNA gyrase B was ascertained by molecular docking studies.

Synthesis, Biological Evaluation, and Molecular Docking of New Benzimidazole-1,2,3-Triazole Hybrids as Antibacterial and Antitumor Agents

A new series of benzimidazole-1,2,3-triazole hybrids have been successfully accomplished by the Click chemistry of different aromatic azides and propargylated benzimidazole (4). The structural confirmations of the molecules were done by NMR, mass spectrometry, IR, and other techniques. All the newly synthesized compounds were tested for their antibacterial potentialities against two Gram-positive and two Gram-negative bacterial strains. The antibacterial results displayed comparable activity of two compounds (7) and (9) with the standard drug against S. aureus and S. epidermidis. The anticancer results showed that compounds (6, 7, 10, and 14) were more promising than tamoxifen toward MCF-7 cells. Whereas, compound (6) was the most potent molecule with IC50 3.23, 6.56, and 5.35 μM toward MCF-7, HepG2, and HCT-116 cell lines, respectively. The molecular docking showed that the synthesized molecules 6, 7, 10, and 14 with promising cytotoxicity displayed similar interaction like erlotinib with EGFR protein. These results suggest that these benzimidazole derivatives are promising lead molecules for chemotherapeutics and microbial infections.

Mesoionische Imine (MIIs): Starke Donoren und vielseitige Liganden für Übergangsmetalle und Hauptgruppensubstrate

AbstractWir berichten über die Synthese und die Reaktivität mesoionischer Imine (MIIs) des 1,2,3‐Triazolin‐5‐imin Typs. Die MIIs sind über eine Basen‐mediierte Cycloaddition eines substituierten Acetonitrils mit einem aromatischen Azid, Methylierung nach etablierten Methylierungsrouten und anschließender Deprotonierung zugänglich. C=O‐Streckschwingungen in MII−CO2− und −Rh(CO)2Cl‐Komplexen wurden bemüht um die Gesamtdonorstärke zu bestimmen. Die MIIs sind stärkere Donoren als N‐Heterocyclische Imine (NHIs). MIIs sind exzellente Liganden für Hauptgruppenelemente und Übergangsmetalle, in welchen sie Substituenten‐induzierte Fluor‐spezifische Wechselwirkungen zeigen oder C−H‐Aktvierungen eingehen. DFT‐Berechnungen haben Einblicke in die Grenzorbitale der MIIs gegeben. Die Rechnungen sagen im Vergleich zu verwandten Liganden eine relative kleine HOMO–LUMO Lücke vorraus. MIIs können potentiell sowohl als π‐Donor‐ als auch π‐Akzeptorliganden wirken. Dieser Bericht demonstiert das Potential von MIIs spannende Eigenschaften mit einem gewaltigen Zukunftspotential zu entwickeln.

Mesoionic Imines (MIIs): Strong Donors and Versatile Ligands for Transition Metals and Main Group Substrates.

We report the synthesis and the reactivity of 1,2,3‐triazolin‐5‐imine type mesoionic imines (MIIs). The MIIs are accessible by a base‐mediated cycloaddition between a substituted acetonitrile and an aromatic azide, methylation by established routes and subsequent deprotonation. C=O‐stretching frequencies in MII−CO2 and −Rh(CO)2Cl complexes were used to determine the overall donor strength. The MIIs are stronger donors than the N‐heterocyclic imines (NHIs). MIIs are excellent ligands for main group elements and transition metals in which they display substituent‐induced fluorine‐specific interactions and undergo C−H activation. DFT calculations gave insights into the frontier orbitals of the MIIs. The calculations predict a relatively small HOMO–LUMO gap compared to other related ligands. MIIs are potentially able to act as both π‐donor and π‐acceptor ligands. This report highlights the potential of MIIs to display exciting properties with a huge potential for future development.

Arenediazonium sulfonates: synthesis, comparison of structural and physicochemical properties

Aromatic diazonium salts are important building blocks in organic synthesis. The present review is concerned with such aromatic diazonium sulfonates as tosylates, dodecylbenzenesulfonates, triflates, camphorsulfonates, silica sulfates. The first part of the review provides information on the synthesis and application of these diazonium salts. It is shown that these diazonium compounds are easily synthesized by diazotization of anilines with sodium nitrite or alkyl nitrites in the presence of corresponding sulfonic acids with high yields. These diazonium salts have found wide application in the synthesis of aromatic azides, halides, triazenes, azo dyes, stilbenes, biaryls, etc. The second part of the article presents information on the comparison of the results of X-ray analysis, infrared spectroscopy and thermal analysis. The structure of diazonium sulfonate salts corresponds to the structure of classical diazonium salts (chlorides, sulfates, tetrafluoroborates). A significant difference between arenediazonium sulfonates and other diazonium salts is their explosion safety and stability in an individual form. Arenediazonium tosylates, triflates and camphorasulfonates are easily soluble both in water and in polar organic solvents. Arenediazonium dodecylbenzenesulfonates are soluble in nonpolar organic media. These features of sulfonate salts are paramount for distinguishing characteristics of the effect of the acid anion on the stability, solubility and reactivity of diazonium salts.