Novel Bis-1,2,3-triazole-thiazolidinone hybrid as anticancer agents that induce apoptosis and molecular modeling study.

Aim: A series of (R)-Carvone-based 1,2,3-triazole-thiazolidinone 17a-h hybrids were synthesized and characterized by spectroscopic techniques NMR and HRMS. The chemical reactivity and the stability parameters were observed via DFT.Method/results: The objective was to evaluate the anticancer activity of the synthesized compounds against cancer cell lines. The mechanism of action by which the 17b and 17g exert their effect suggested that they may induce apoptosis through activation of caspase-3/7. This effect was observed against the most important NIMA-related kinases via Docking investigation. The designed compounds were identified as the best inhibitors of the NEK family via the inactivation of the caspase-3. The Docking results were supported by Dynamics where the binding energies justified the medicinal importance of the synthesized derivatives.

[Box: see text].

Step-by-step synthetic route to access eugenol-1,2,3-triazole-chalcone hybrid.

Molecular hybridization represents a strategic approach in drug design, where two or more pharmacophoric elements from distinct bioactive molecules are integrated into a single hybrid compound. In this study, we synthesized hybrid compounds of chalcone, triazole, and eugenol through straightforward reactions using 4-hydroxyacetophenone as the starting material. Initially, 4-hydroxyacetophenone (1) underwent alkylation with 1,4-dibromobutane to produce compound 2 with an 84 % yield. Compound 2 was then subjected to azidation, resulting in azidobutoxyacetophenone 3 with a 71 % yield. Subsequently, compound 3 was reacted with either benzaldehyde or 4-methoxybenzaldehyde via base-catalyzed aldol condensation, yielding azidobutoxychalcones 4a (69 %) and 4b (84 %). Finally, azide-alkyne [3+2] cycloaddition between 4a/4b and propargylated eugenol afforded chalcone derivatives bearing eugenol-1,2,3-triazole hybrids 5a and 5b, each with a 90 % yield.•Synthesized chalcones featuring an eugenol-1,2,3-triazole scaffold using 4-hydroxyacetophenone as the starting material.•Synthesis was accomplished through a four-step reaction sequence.•Products were obtained in good yield.

Study on interaction with high-abundant blood proteins and identification of low-abundant proteins to 5-phenyl-1-(p-tolyl)-1 H-1,2,3-triazole by serum proteomics.

In this study, a comprehensive investigation was undertaken to elucidate a simple triazole compound, 5-phenyl-1-(p-tolyl)-1 H-1,2,3-triazole (PPTT), its interactions with high-abundant proteins and identification of low-abundant proteins by serum proteomics. Employing a combination of spectroscopic techniques and computational chemistry, the interactions between PPTT and three high-abundance blood globular proteins, namely human serum albumin (HSA), human immunoglobulin G (HIgG), and hemoglobin (BHb), were explored, thereby ascertaining their binding constants and thermodynamic parameters at the molecular level. Subsequently, based on the differential proteomics, utilizing two-dimensional gel electrophoresis (2-DE) in conjunction with matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS), the research team isolated and identified differentially expressed low-abundance proteins in human blood serum samples following exposure to PPTT. The results showed that there were twenty highly expressed proteins identified from blood serum samples intervened by PPTT. Combining bioinformatics techniques, these proteins were classified, providing preliminary insights like preproprotein or precursors inhibiting the activity of elastase, defending and regulating the immune system, carrying lipid, and other functions into their biological functionalities. One of the differential proteins, apolipoprotein A-1 (ApoA-1) protein, was selected as a possible target to explore the mechanism of action of PPTT intervention on the related signaling pathways involved in human hepatocellular carcinomas(Hep G2) cells. These research findings offer scientifically sound guidance for further in-depth exploration, development, and application of the 1,2,3-triazole compound.

Design, Synthesis, and Anticancer and Antibacterial Activities of Quinoline-5-Sulfonamides.

A series of new unique acetylene derivatives of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonamide 3a-f and 6a-f were prepared by reactions of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonyl chlorides with acetylene derivatives of amine. A series of new hybrid systems containing quinoline and 1,2,3-triazole systems 7a-h were obtained by reactions of acetylene derivatives of quinoline-5-sulfonamide 6a-d with organic azides. The structures of the obtained compounds were confirmed by 1H and 13C NMR spectroscopy and HR-MS spectrometry. The obtained quinoline derivatives 3a-f and 6a-f and 1,2,3-triazole derivatives 7a-h were tested for their anticancer and antimicrobial activity. Human amelanotic melanoma cells (C-32), human breast adenocarcinoma cells (MDA-MB-231), and human lung adenocarcinoma cells (A549) were selected as tested cancer lines, while cytotoxicity was investigated on normal human dermal fibroblasts (HFF-1). All the compounds were also tested against reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and representatives of multidrug-resistant clinical isolates of methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis. Only the acetylene derivatives of 8-hydroxyquinoline-5-sulfonamide 3a-f were shown to be biologically active, and 8-hydroxy-N-methyl-N-(prop-2-yn-1-yl)quinoline-5-sulfonamide (3c) showed the highest activity against all three cancer lines and MRSA isolates. Its efficacies were comparable to those of cisplatin/doxorubicin and oxacillin/ciprofloxacin. In the non-cancer HFF-1 line, the compound showed no toxicity up to an IC50 of 100 µM. In additional tests, compound 3c decreased the expression of H3, increased the transcriptional activity of cell cycle regulators (P53 and P21 proteins), and altered the expression of BCL-2 and BAX genes in all cancer lines. The unsubstituted phenolic group at position 8 of the quinoline is the key structural fragment necessary for biological activity.

Design, synthesis, and antitumor activity evaluation of 1,2,3-triazole derivatives as potent PD-1/PD-L1 inhibitors.

A series of 1,2,3-triazole derivatives targeting the PD-1/PD-L1 pathway were designed, synthesized, and evaluated both in vitro and in vivo. Among them, compound III-4 demonstrated exceptional inhibitory activity against the interaction of PD-1/PD-L1 and showed great binding affinity with hPD-L1, with an IC50 value of 2.9 nM and a KD value of 3.33 nM. In the co-culture of Hep3B/OS-8/hPD-L1 cells and CD3+ T cells assay, III-4 relieved the inhibition of PD-L1 on PD-1 and promoted the expression of IFN-γ, which shared a comparable effect to that of the PD-1 monoclonal antibody Pembrolizumab (5 µg/mL). Moreover, compound III-5, an ester prodrug derived from III-4, demonstrated significant antitumor effects in the hPD-L1-MC38 C57BL/6 mouse model (TGI: 49.6 %) by oral administration. These findings suggest that compound III-5 holds promise as an inhibitor of the PD-1/PD-L1 interaction for cancer immunotherapy.

Synthesis of novel 1,2,3-triazole-tethered N-acyl hydrazones as a new class of carbonic anhydrase II inhibitors: In vitro and in silico potentials.

Carbonic anhydrase II (CA II) is crucial for maintaining homeostasis in several processes, including respiration, lipogenesis, gluconeogenesis, calcification, bone resorption, and electrolyte balance. It is a pivotal druggable target which is implicated in glaucoma, renal, gastric, and pancreatic carcinomas, as well as in malignant brain tumours. Therefore, to identify new CA II (bovine) inhibitors, the current study was designed to synthesize a library of 20 new triazole-linked hydrazones (6a-t). All compounds were characterized by using spectroscopic techniques such as NMR and mass spectrometry. The in-vitro evaluation resulted in impressive inhibitory capability against CA II with IC50 values ranging from 9.10 ± 0.26-48.26 ± 1.30 µM. Among all derivatives, compounds 6a, 6b, 6d, 6k-6m, 6q, 6s and 6t exhibited potent inhibitory potential with 6t deemed as the most active inhibitor. Additionally, kinetic study of the hybrid 6t revealed concentration dependent type of inhibition with Ki value 7.24 ± 0.0086 µM. Furthermore, molecular docking of 6t correlates well with the kinetic analysis. The in-silico ADMET indicated that most of the synthesized compounds have properties conducive to drug development.

Discovery of new quinoline derivatives bearing 1-aryl-1,2,3-triazole motif as influenza H1N1 virus neuraminidase inhibitors.

Sporadically and periodically, influenza outbreaks threaten global health and the economy. Antigen drift-induced influenza virus mutations hamper antiviral drug development. Thus, a novel antiviral agent is urgently needed to address medication inefficacy issues. Herein, sixteen new quinoline-triazole hybrids 6a-h and 9a-h were prepared and evaluated in vitro against the H1N1 virus. In particular, 6d, 6e, and 9b showed promising H1N1 antiviral activity with selective index (SI) CC50/IC50 values of 15.8, 37, and 29.15. After that, the inhibition rates for various mechanisms of action (virus replication, adsorption, and virucidal activity) were investigated for the most efficient candidates 6d, 6e, and 9b. Additionally, their ability to inhibit neuraminidase was evaluated. With an IC50 value of 0.30 µM, hybrid 6d demonstrated effective and comparable inhibitory activity to Oseltamivir. Ultimately, molecular modeling investigations, encompassing molecular docking and molecular dynamic simulations, were conducted to provide a scientific basis for the observed antiviral results.

Design, Synthesis, Evaluation of Antitubercular Activity and Insilco Studies of Novel 1,5-Naphthyridin-2(1H)-one Pendent 1,2,3-Triazoles.

A library of 1,5-Naphthyridin-2(1H)-one based 1,2,3-triazole analogues (11a-q) were synthesized via series of reactions such as protection, oxidation, cyclization and click chemistry. The new molecules were tested for their antitubercular activity against M. tuberculosis mc26230 and determined the minimum inhibitory concentration (MIC90) employing Rifampicin as reference. The 3-cyano and 4-cyano substituted analogues 11e and 11f displayed superior activity with an MIC value of 4.0 µg/ml. Additionally, these potent molecules were tested for determination of their MBC values and ATP depletion assay showed a hopeful relative luminescence. Additionally, determined the MIC of 11e and 11f against multi-drug resistant strains of M. Tuberculosis viz.mc2 8243, mc2 8247 and mc2 8259. The cytotoxicity of these two molecules presented no effects on normal cell. The profound results of these two molecules proved them as potential antitubercular agent. Further, molecular docking studies were portrayed against crystal structure of M. Tuberculosis dihydrofolate reductase which garnered promising docking scores and binding interactions such as H-bond and hydrophobic. ADME prediction revealed their favorable drug-likeness characteristics.

Design, Synthesis, and Bioactivity Determination of Novel Malononitrile Derivatives Containing 1,2,3-Triazole.

Using antifungal agrochemicals as the most economical solution might reduce plant diseases caused by pathogenic fungi, which have a significant negative impact on the quality and yield of food worldwide. In this work, 33 compounds (G) containing 1,2,3-triazole and malononitrile structures were synthesized. When the compounds were tested in vitro against six fungal species, they exhibited significant fungicidal activity toward Botrytis cinerea and Rhizoctonia solani. Compounds G17 and G30 displayed promising in vivo efficacy, with an EC50 of 0.19 and 0.27 mg/L respectively against R. solani. Fungal ergosterol production was suppressed by compounds G17 and G30, according to a preliminary analysis of their mechanism of action on R. solani using transcriptomics and scanning electron microscopy. It has been shown through experimentation that compounds G17 and G30 prevent R. solani from synthesizing ergosterol. Ultimately, it was anticipated that compounds G17 and G30 would be discovered to be low-toxic.

Design of new α-glucosidase inhibitors based on the bis-4-hydroxycoumarin skeleton: Synthesis, evaluation, and in silico studies.

In this work, we have reported the design, synthesis, in vitro, and in silico enzymatic evaluation of new bis-4-hydroxycoumarin-based phenoxy-1,2,3-triazole-N-phenylacetamide derivatives 5a-m as potent α-glucosidase inhibitors. All the synthesized analogues showed high inhibition effects against α-glucosidase (IC50 values ranging between 6.0 ± 0.2 and 85.4 ± 2.3 µM) as compared to the positive control acarbose (IC50 = 750.0 ± 0.6 µM). Among the newly synthesized compounds 5a-m, 2,4-dichloro-N-phenylacetamide derivative 5i with inhibition effect around 125-folds more than the acarbose was identified as the most potent entry. A structure-activity relationship (SAR) study about the title compounds 5a-m demonstrated that the inhibition effects of these compounds depend on the pattern of substitution on the N-phenylacetamide ring. The interaction modes and binding energies in the active site of enzyme of the important analogues (in term of SAR study) were evaluated through molecular docking study. Molecular dynamics and prediction of pharmacokinetic properties and toxicity of the most potent compound 5i also evaluated and the obtained data was compared with the acarbose.

Two step one-pot synthesis of 7-azaindole linked 1,2,3-triazole hybrids: In-vitro and in-silico antimicrobial evaluation.

Herein, we report design, synthesis and characterization of a new library of 7-azaindole N-ethyl linked 1,2,3-triazoles containing ethylene as a spacer unit, and evaluation of all the synthesized compounds for their antimicrobial properties. Antibacterial potential was checked against two Gram positive (B. subtilis and S. aureus) and two Gram negative (E. coli and P. aeruginosa) bacterial strains while antifungal potential was assayed against two fungal strains (C. albicans and A. niger). All the tested compounds showed satisfactory antibacterial potency in comparison to reference drug ciprofloxacin with MIC values ranging from 0.0108 to 0.0432 µmol/mL. Interestingly, except two, all the target compounds showed better antifungal property as compared to the reference drug fluconazole with MIC values less than 0.0408 µmol/mL. One of the compounds exhibited two-fold better antifungal potential in comparison to fluconazole. Furthermore, in-silico ADMET and DFT studies reported drug likeness behavior and chemical reactivity parameters, respectively. The cytotoxicity results on substrate azide 3 and most potent 1,2,3-triazoles (5d and 5l) were found to be non-toxic.

Click-chemistry-inspired synthesis of new series of 1,2,3-triazole fused chromene with glucose triazole conjugates: Antibacterial activity assessment with molecular docking evaluation.

A series of new 1,2,3-triazole fused chromene based glucose triazole conjugates were synthesized from chromene fused 1,2,3-triazolyl extended alkyne and 2,3,4,6-tetra-O-acetyl-ß-d-glucopyranosyl azide in good to excellent yield by a copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The major advantages include mild reaction conditions, high yield, good substrate scope, and shorter reaction time. The antibacterial efficacy of the compounds were assessed in vitro against human pathogenic Gram-negative E. coli and Gram-positive S. aureus bacteria. Compound 24j was found to be the most potent molecule with zone of inhibition (ZI) of 17 mm and minimum inhibitory concentration (MIC) of 25 µg mL-1 in E. coli and ZI of 16 mm and MIC of 25 µg mL-1 in S. aureus. Also, it significantly inhibited E. coli DNA-gyrase in silico with a binding affinity of -9.4 kcal/mol. Among all the synthesized compounds, 24i, 24d, 24e and 24f showed significant antibacterial activity against both strains and inhibited DNA-gyrase in silico with good binding affinities. Hence, these 1,2,3-triazole fused chromene based glucose triazole conjugates may evolve to be powerful antibacterial agents in recent future, according to structure-activity relationships based on strong antibacterial properties and molecular docking studies.

Synthesis, crystal structure and Hirshfeld surface analysis of [1-(4-bromo-phen-yl)-1H-1,2,3-triazol-4-yl]methyl 2-(4-nitro-phen-oxy)acetate.

The title compound, C17H13BrN4O5, was synthesized by a Cu2Br2-catalysed Meldal-Sharpless reaction between 4-nitro-phen-oxy-acetic acid propargyl ether and para-bromo-phenyl-azide, and characterized by X-ray structure determination and 1H NMR spectroscopy. The mol-ecules, with a near-perpendicular orientation of the bromo-phenyl-triazole and nitro-phen-oxy-acetate fragments, are connected into a three-dimensional network by inter-molecular C-H⋯O and C-H⋯N hydrogen bonds (confirmed by Hirshfeld surface analysis), π-π and Br-π inter-actions.

Molecular Docking and Molecular Dynamics Simulations of Synthesized Thiazole-Isatin-1,2,3-triazole Hybrids as Promising Inhibitors for DNA Gyrase and Sterol 14α-Demethylase.

In the present work, a new class of thiazole-isatin-1,2,3-triazole hybrids (5 a-5 p) and precursor alkyne hybrids (6 a-6 d) has been reported with their in-silico studies. After structural identifications using different spectroscopic technique such as FTIR, 1H and 13C NMR and HRMS, the synthesized hybrids were explored for their biological potential using molecular docking and molecular dynamics calculations. Molecular docking results revealed that compound 5 j showed maximum binding energy i. e. -10.3 and -12.6 kcal/mol against antibacterial and antifungal enzymes; 1KZN (E. coli) and 5TZ1 (C. albicans), respectively. Molecular dynamics simulations for the best molecule (100 ns) followed by PBSA calculations suggested a stable complex of 5 j with 5TZ1 with binding energy of -118.760 kJ/mol as compared to 1KZN (-94.593 kJ/mol). The mean RMSD values for the 1KZN with 5 j complex remained approximately 0.175 nm throughout all the time span of 100 ns in the production stages and is in the acceptable range. Whereas, 5TZ1 with 5 j complex, RMSD values exhibited variability within the range of 0.15-0.25 nm.

Pyrazoline Spiro-oxindole tethered 1,2,3-triazole hybrids: Design, synthesis, antimicrobial efficacy and molecular modelling studies.

Inspired from the important applications of spirocyclic compounds in medicinal chemistry, a new series of pyrazoline Spiro-oxindole tethered 1,2,3-triazole hybrids was reported via Cu(I)-catalyzed click reaction from isatin-pyrazoline linked terminal alkynes with in situ derived benzyl azides. Antimicrobial evaluation data showed that all hybrids exhibited promising efficacy towards the tested microbial strains. Antimicrobial screening as well as docking studies suggested that hybrid 6a was found to be most potent towards Aspergillus niger (MIC = 0.0122 µmol/mL) and Escherichia coli (MIC = 0.0061 µmol/mL). Molecular docking studies of 6a within the binding pockets of antibacterial and antifungal targets revealed good interactions with the binding energies of - 144.544 kcal/mol and - 154.364 kcal/mol against 1KZN (E. coli) and 3D3Z (A. niger), respectively. Further, MD simulations were performed to study the stability of the complexes formed at 300 K. Based on the RMSD trajectories, it is evident that 3D3Z-6a complex exhibits minimal deviation, whereas the 1KZN-6a complex displayed little more deviation compared to the protein but, both are in acceptable range. Moreover, 3D3Z-6a and 1KZN-6a showed maximum number of hydrogen bonds at 50 ns and 70 ns, respectively, thereby complementing the stability of these complexes.

Synthesis and In Silico Analysis of New Polyheterocyclic Molecules Derived from [1,4]-Benzoxazin-3-one and Their Inhibitory Effect against Pancreatic α-Amylase and Intestinal α-Glucosidase.

This study focuses on synthesizing a new series of isoxazolinyl-1,2,3-triazolyl-[1,4]-benzoxazin-3-one derivatives 5a-5o. The synthesis method involves a double 1,3-dipolar cycloaddition reaction following a "click chemistry" approach, starting from the respective [1,4]-benzoxazin-3-ones. Additionally, the study aims to evaluate the antidiabetic potential of these newly synthesized compounds through in silico methods. This synthesis approach allows for the combination of three heterocyclic components: [1,4]-benzoxazin-3-one, 1,2,3-triazole, and isoxazoline, known for their diverse biological activities. The synthesis procedure involved a two-step process. Firstly, a 1,3-dipolar cycloaddition reaction was performed involving the propargylic moiety linked to the [1,4]-benzoxazin-3-one and the allylic azide. Secondly, a second cycloaddition reaction was conducted using the product from the first step, containing the allylic part and an oxime. The synthesized compounds were thoroughly characterized using spectroscopic methods, including 1H NMR, 13C NMR, DEPT-135, and IR. This molecular docking method revealed a promising antidiabetic potential of the synthesized compounds, particularly against two key diabetes-related enzymes: pancreatic α-amylase, with the two synthetic molecules 5a and 5o showing the highest affinity values of 9.2 and 9.1 kcal/mol, respectively, and intestinal α-glucosidase, with the two synthetic molecules 5n and 5e showing the highest affinity values of -9.9 and -9.6 kcal/mol, respectively. Indeed, the synthesized compounds have shown significant potential as antidiabetic agents, as indicated by molecular docking studies against the enzymes α-amylase and α-glucosidase. Additionally, ADME analyses have revealed that all the synthetic compounds examined in our study demonstrate high intestinal absorption, meet Lipinski's criteria, and fall within the required range for oral bioavailability, indicating their potential suitability for oral drug development.

Design, synthesis, in vitro, and in silico anti-α-glucosidase assays of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives as new anti-diabetic agents.

In this work, a novel series of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives 5a-n were designed by consideration of the potent α-glucosidase inhibitors containing indole and carboxamide-1,2,3-triazole-N-phenylacetamide moieties. These compounds were synthesized by click reaction and evaluated against yeast α-glucosidase. All the newly title compounds demonstrated superior potency when compared with acarbose as a standard inhibitor. Particularly, compound 5k possessed the best inhibitory activity against α-glucosidase with around a 28-fold improvement in the inhibition effect in comparison standard inhibitor. This compound showed a competitive type of inhibition in the kinetics. The molecular docking and dynamics demonstrated that compound 5k with a favorable binding energy well occupied the active site of α-glucosidase.

Recent Developments in 1,2,3-Triazole Based α-Glucosidase Inhibitors: Design Strategies, Structure-Activity Relationship and Mechanistic Insights.

Diabetes mellitus is a chronic and most prevalent metabolic disorder affecting 422 million the people worldwide and causing life-threatening associated conditions including disorders of kidney, heart, and nervous system as well as leg amputation and retinopathy. Steadily rising cases from the last few decades suggest the failure of currently available drugs in containment of this disease. α-Glucosidase is a potential target for effectively tackling this disease and attracting significant interest from medicinal chemists around the globe. Besides having a set of side effects, currently available α-glucosidase inhibitors (carbohydrate mimics) offer better tolerability, safety, and synergistic pharmacological outcomes with other antidiabetic drugs therefore medicinal chemists have working extensively over last three decades for developing alternative α-glucosidase inhibitors. The 1,2,3-Triazole nucleus is energetically used by various research groups around the globe for the development of α-glucosidase inhibitors posing it as an optimum scaffold in the field of antidiabetic drug development. This review is a systematic analysis of α-glucosidase inhibitors developed by employing 1,2,3-triazole scaffold with special focus on design strategies, structure-activity relationships, and mechanism of inhibitory effect. This article will act as lantern for medicinal chemists in developing of potent, safer, and effective α-glucosidase inhibitors with desired properties and improved therapeutic efficacy.

Benzothiazole-Quinoline-Based Fluorescent Probe for Fe3+ and its Applications in Environmental and Biological Samples.

Due to the its high abundance, iron ion contamination and toxicity is one of the most challenging issue for living beings. Although, iron is extremenly important for several body functions, excess amount of iron in the body can also be fatal. In last century, rapid industrialization, iron extraction and mismanagement of industrial waste disposal leads to iron contamination in water bodies. Therefore, versatile iron sensors needs to be develop which can be employed for detection in biological as well as real water samples. 8-hydroxyquinoline is well-known for its strong affinity towards transition metals including Fe3+. In this regard, we have synthesised benzothiazole-quinoline derived 1,2,3- triazole (4HBTHQTz), in which 4-(benzo[d]thiazol-2-yl)phenolic (4-HBT) group acts as a fluorophore. 4HBTHQTz showed high fluorescence and induced a selective decrease in fluorescence with Fe3+ at 380 nm (λex. = 320 nm). The detection limit of 4HBTHQTz with Fe3+ is calculated as 0.64 µM, which is lower than the WHO recommended limit in drinking water. 4HBTHQTz works over the 5-8 pH range and has shown promising results for quantitative detection of Fe3+ in water samples collected from tap, river and seawater. 4HBTHQTz can also detect the Fe3+ in biological samples which is confirmed by fluorescence cell imaging using L929 mouse fibroblast cells. Overall, 4HBTHQTz showed advantages such as high selectivity, quick detection, and good limit of detection (LOD) for Fe3+.

Density Function Theory Study on the Energy and Circular Dichroism Spectrum for Methylene-Linked Triazole Diads Depending on the Substitution Position and Conformation.

Since the discovery of metal-catalyzed azide-alkyne cycloadditions, 1,2,3-triazoles have been widely used as linkers for various residues. 1,2,3-Triazole is an aromatic five-membered cyclic compound consisting of three nitrogen and two carbon atoms with large dipoles that absorb UV light. In the past decade, we have been working on the synthesis of dense triazole polymers possessing many 1,2,3-triazole residues linked through a carbon atom in their backbone as a new type of functional polymer. Recently, we reported that stereoregular dense triazole uniform oligomers exhibit a circular dichroism signal based on the chiral arrangement of two neighboring 1,2,3-triazole residues. In this study, to investigate the chiral conformation of two neighboring 1,2,3-triazole residues in stereoregular dense triazole uniform oligomers, density functional theory (DFT) calculations were performed using 1,2,3-triazole diads with different substitution positions and conformations as model compounds and compared with our previous results.