Synthesis of 1H-1,2,3-triazole derivatives as new α-glucosidase inhibitors and their molecular docking studies

Dihydrofolate reductase inhibitory potential of 1H-indole-based-meldrum linked 1H-1,2,3-triazoles as new anticancer derivatives: In-vitro and in-silico studies

In this present work, we describe the syntheses of a new series of 32 1H-indole-based-meldrum linked 1H-1,2,3-triazole derivatives (2-13, 15a-15f, 16a-16f, 17a-17f and 19a, 19b, 20a), which constitute a new class of 1H-1,2,3-triazoles. Compounds 15a-15f, 16a-16f, 17a-17f have been prepared by employing "click" reactions between substituted 1H-indole-based meldrum alkynes (11, 12 and 13) and substituted aromatic azides (14a-14f) in the presence of copper iodide (CuI) and Hünig's base. Then, the synthesis of compounds 19, 20 through decomposition of meldrum moiety. The resulting compounds have been screened for their dihydrofolate reductase (DHFR) inhibition activity. All the newly synthesized compounds were characterized by 1H NMR, 13C NMR, 19F NMR (spectroscopy when applicable), and HR-ESI-MS spectroscopy techniques. The X-ray crystallography studies have unambiguously confirmed the structure of compounds 6, 11 and 13. Furthermore, their DHFR-inhibitory activity was evaluated in-vitro. The results obtained from the DHFR-inhibitory assay revealed that all the synthesized 1H-indole-based-meldrum linked 1H-1,2,3-triazole derivatives were highly potent inhibitors, with IC50 values in the range 3.48 ± 0.16-30.37 ± 1.20 μM. Ten compounds (15c-15f, 16c-16f, 17e and 17f) among the 32 synthesized 1H-indole-based-meldrum linked 1H-1,2,3-triazole compounds were found to exhibit exceptional inhibitory while the rest of the derivatives showed moderate activities. Additionally, molecular docking analysis of the most active (16f), moderate (15c) and least active (16a) inhibitors reflect excellent binding of 16f with the binding residues of DHFR with higher docking score (-9.13 kcal/mol) than that of 15c and 16a. The docking analysis correlates well with the inhibitory potential of these synthesized molecules. Overall, this study may pave the way to medicinal analogues of 1H-indole-based-meldrum linked 1H-1,2,3-triazoles as potent DHFR inhibition activity.

An insight on medicinal attributes of 1,2,3- and 1,2,4-triazole derivatives as alpha-amylase and alpha-glucosidase inhibitors

Diabetes Mellitus (DM) is the globe's common leading disease which is caused by high consumption of glucose. DM compiles groups of metabolic disorders which are characterized by inadequate secretion of insulin from pancreas, resulting in hyperglycemia condition. Many enzymes play a vital role in the metabolism of carbohydrate known as α-amylase and α-glucosidase which is calcium metalloenzyme that leads to breakdown of complex polysaccharides into glucose. To tackle this problem, search for newer antidiabetic drugs is the utmost need for the treatment and/or management of increasing diabetic burden. The inhibition of α-amylase and α-glucosidase is one of the effective therapeutic approaches for the development of antidiabetic therapeutics. The exhaustive literature survey has shown the importance of medicinally privileged triazole specifically 1,2,3-triazol and 1,2,4-triazoles scaffold tethered, fused and/or clubbed with other heterocyclic rings structures as promising agents for designing and development of novel antidiabetic therapeutics. Molecular hybrids namely pyridazine-triazole, pyrazoline-triazole, benzothiazole-triazole, benzimidazole-triazole, curcumin-triazole, (bis)coumarin-triazole, acridine-9-carboxamide linked triazole, quinazolinone-triazole, xanthone-triazole, thiazolo-triazole, thiosemicarbazide-triazole, and indole clubbed-triazole are few examples which have shown promising antidiabetic activity by inhibiting α-amylase and/or α-glucosidase. The present review summarizes the structure-activity relationship (SAR), enzyme inhibitory activity including IC50 values, percentage inhibition, kinetic studies, molecular docking studies, and patents filed of the both scaffolds as alpha-amylase and alpha-glucosidase inhibitors, which may be used for further development of potent inhibitors against both enzymes.

Dynamics of small molecule-enzyme interactions: Novel benzenesulfonamides as multi-target agents endowed with inhibitory effects against some metabolic enzymes

In contemporary medicinal chemistry, employing a singular small molecule to concurrently multi-target disparate molecular entities is emerging as a potent strategy in the ongoing battle against metabolic disease. In this study, we present the meticulous design, synthesis, and comprehensive biological evaluation of a novel series of 1,2,3-triazolylmethylthio-1,3,4-oxadiazolylbenzenesulfonamide derivatives (8a-m) as potential multi-target inhibitors against human carbonic anhydrase (EC.4.2.1.1, hCA I/II), α-glycosidase (EC.3.2.1.20, α-GLY), and α-amylase (EC.3.2.1.1, α-AMY). Each synthesized sulfonamide underwent rigorous assessment for inhibitory effects against four distinct enzymes, revealing varying degrees of hCA I/II, a-GLY, and a-AMY inhibition across the tested compounds. hCA I was notably susceptible to inhibition by all compounds, demonstrating remarkably low inhibition constants (KI) ranging from 42.20 ± 3.90 nM to 217.90 ± 11.81 nM compared to the reference standard AAZ (KI of 439.17 ± 9.30 nM). The evaluation against hCA II showed that most of the synthesized compounds exhibited potent inhibition effects with KI values spanning the nanomolar range 16.44 ± 1.53-70.82 ± 4.51 nM, while three specific compounds, namely 8a-b and 8d, showcased lower inhibitory potency than other derivatives that did not exceed that of the reference drug AAZ (with a KI of 98.28 ± 1.69 nM). Moreover, across the spectrum of synthesized compounds, potent inhibition profiles were observed against diabetes mellitus-associated α-GLY (KI values spanning from 0.54 ± 0.06 μM to 5.48 ± 0.50 μM), while significant inhibition effects were noted against α-AMY, with IC50 values ranging between 0.16 ± 0.04 μM and 7.81 ± 0.51 μM) compared to reference standard ACR (KI of 23.53 ± 2.72 μM and IC50 of 48.17 ± 2.34 μM, respectively). Subsequently, these inhibitors were evaluated for their DPPH· and ABTS+· radical scavenging activity. Moreover, molecular docking investigations were meticulously conducted within the active sites of hCA I/II, α-GLY, and α-AMY to provide comprehensive elucidation and rationale for the observed inhibitory outcomes.

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.

Synthesis, antidiabetic activity and molecular docking studies of novel aryl benzylidenethiazolidine-2,4-dione based 1,2,3-triazoles

A series of novel aryl benzylidenethiazolidine-2,4-dione based 1,2,3-triazoles synthesized in a straightforward route consisting of benzylidenethiazolidine-2,4-dione and 1,2,3-triazole pharmacophores. The new scaffolds tested for in vitro antidiabetic activity by inhibition of aldose reductase enzyme and its inhibition measured in half of Inhibition Concentration (IC50). The activity results correlated with standard reference Sorbinil (IC50: 3.45 ± 0.25 µM). Among all the titled compounds 8f (1.42 ± 0.21 µM), 8d (1.85 ± 0.39 µM), 13a (1.94 ± 0.27 µM) and 8b (1.98 ± 0.58 µM) shown potent activity. In addition, molecular docking results against the crystal structure of aldose reductase (PDB ID: 1PWM) revealed that the binding affinities shown by all synthesized compounds are higher than the reference compound Sorbinil. The docking scores, H-bond interactions, and hydrophobic interactions well defined inhibition strength of all compounds.

Biochemical and computational inhibition of α-glucosidase by novel metronidazole-linked 1H-1,2,3-triazole and carboxylate moieties: kinetics and dynamic investigations

In the current study, metronidazole derivatives containing 1H-1,2,3-triazole and carboxylate moieties were evaluated in vitro and by computational methods for their anti-diabetic potential to insight into their medicinal use for the management of type II diabetes mellitus. Interestingly all 14 compounds displayed high to significant inhibitory capability against the key carbohydrate's digestive enzyme α-glucosidase with IC50 values in range of 9.73-56.39 μM, as compared to marketed drug acarbose (IC50 = 873.34 ± 1.67 μM). Compounds 5i and 7c exhibited the highest inhibition, therefore, these two compounds were further evaluated for their mechanistic studies to explore its type of inhibition. Compounds 5i and 7c both displayed a concentration-dependent (competitive type of inhibition) with Ki values 7.14 ± 0.01, 6.15 ± 0.02 μM, respectively, which conclude their favourable interactions with the active site residues of the α-glucosidase. Interestingly all compounds are non-cytotoxic against BJ cell line. To further validate our findings, in-silico approaches like molecular docking, and molecular dynamic simulations were applied to investigate the mode of bindings of compounds with the enzyme and identifies their inhibition mechanism, which strongly complements our experimental findings.Communicated by Ramaswamy H. Sarma.

A Review on the Development of Novel Heterocycles as α-Glucosidase Inhibitors for the Treatment of Type-2 Diabetes Mellitus

One of the most effective therapeutic decencies in the treatment of Type 2 Diabetes Mellitus is the inhibition of α-glucosidase enzyme, which is present at the brush border of the intestine and plays an important role in carbohydrate digestion to form mono-, di-, and polysaccharides. Acarbose, Voglibose, Miglitol, and Erniglitate have been well-known α-glucosidase inhibitors in science since 1990. However, the long synthetic route and side effects of these inhibitors forced the researchers to move their focus to innovate simple and small heterocyclic scaffolds that work as excellent α-glucosidase inhibitors. Moreover, they are also effective against the postprandial hyperglycemic condition in Type 2 Diabetes Mellitus. In this aspect, this review summarizes recent progress in the discovery and development of heterocyclic molecules that have been appraised to show outstanding inhibition of α-glucosidase to yield positive effects against diabetes.

Intramolecular Click Cycloaddition Reactions: Synthesis of 1,2,3-Triazoles

Click Chemistry, as a powerful tool, has been used for the synthesis of a variety of 1,2,3-triazoles. Among click cycloaddition reactions, intramolecular click reactions carried out in azido-alkyne precursors has not been thoroughly reviewed. Hence, in this review, we have summarized and categorised the recent literature (from 2012 on) based on the azidoalkynyl precursor's type and a brief and concise description of the involved mechanisms is presented. Accordingly, we have classified the relevant literature into three categories: (1) substitution precursors (2) addition and (3) multi-component reaction (MCR) products.

Growing Impact of Intramolecular Click Chemistry in Organic Synthesis

Click Chemistry, a modular, rapid, and one of the most reliable tool for the regioselective 1,2,3-triazole forming [3+2] reaction of organic azide and terimal alkyne is widely explored in various emerging domains of research ranging from chemical biology to catalysis and medicinal chemistry to material science. This regioselective reaction from a diverse range of azido-alkyne scaffolds has been well performed in both intermolecular as well as intramolecular fashions. In comparison to the intermolecular metal (Cu/Ru/Ni) variant of 'Click Chemistry', the intramolecular click tool is little addressed. The intramolecular click chemistry is exemplified as a mordern tool of cyclization which involves metal-catalyzed (CuAAC/RuAAC) cyclization, organo-catalyzed cyclization, and thermal-induced topochemical reaction. Thus, we report herein the recent approaches on intramolecular azide-alkyne cycloaddition 'Click Chemistry' with their wide-spread emerging applications in the developement of a diverse range of molecules including fused-heterocycles, well-defined peptidomemics, and macrocyclic architectures of various notable features.

Design, synthesis and antidiabetic study of triazole clubbed indole derivatives as α-glucosidase inhibitors

α -Glucosidase is an enzyme present near the brush boundary of the small intestine that is essential in the hydrolysis of carbohydrates to glucose. Because inhibiting this enzyme slows the release of glucose, α-Glucosidase inhibitors are appealing medications for treating diabetes as a carbohydrate-related illness. The present study includes the design, synthesis and antidiabetic potential of novel triazole based indole derivatives as α-glucosidase inhibitor. Among them, the compound R1 was found to be most potent with promising candidate with IC50 value of 10.1 μM and R2 and R3 showed the good inhibitory potency with IC50 values 12.95 μM, 11.35 μM, respectively when compared to the standard drug acarbose having IC50 value of 13.5 μM. In in vivo studies, body weight of the mice was increased when compared to standard drug acarbose, the blood glucose level of the mice was decreased, same as the total cholesterol level, LDL, and triglycerides level decreased in comparison to standard drug. The level HDL was increased as it is a good cholesterol in comparison to standard drug acarbose. Furthermore, these synthesized compounds were docked with α-glucosidase using PDB ID:3WY1 which showed that compound R1 having good docking score -6.734 kcal/mol and compound R2, R3 showed docking score -6.14, -6.10 kcal/mol, respectively when compared with standard acarbose having docking score -4.55 kcal/mol. R1 showed the similar interaction with amino acid PHE166, GLU271, comparison with standard drug Acarbose. The synthesized compounds have been confirmed for antidiabetic activity and may be used for further development of potent compounds.

Synthesis, biological evaluation, and molecular docking study of chromen-linked hydrazine carbothioamides as potent α-glucosidase inhibitors

Inhibiting α-glucosidase is a reliable method for reducing blood sugar levels in diabetic individuals. Several novel chromen-linked hydrazine carbothioamide (3a-r) were designed and synthesized by condensation of chromone-3-carbaldehyde with a variety of substituted thiosemicarbazides. The structures of these new analogues were elucidated through various advanced spectroscopic techniques (1 H NMR, 13 C NMR, and ESI-MS). The resulted compounds were screened for α-glucosidase inhibitory potential and all the compounds (3a-r) exhibited potent inhibition of α-glucosidase with IC50 values ranging 0.29-53.70 µM. Among them compounds 3c, 3f, 3h, and 3r displayed the highest α-glucosidase inhibitor capability with IC50 values of 1.50, 1.28, 1.08, and 0.29 µM, respectively. Structure-activity relationship showed that different substituted groups are responsible for the variation in the α-glucosidase inhibition. The kinetics studies of the most active inhibitor (3r) were performed, to investigate the mode of inhibition and dissociation constants (Ki), that indicated a competitive inhibitor with Ki value of 1.47 ± 0.31 µM. Furthermore, molecular docking studies was performed to reveal the possible interactions, such as H-bonding, or π-π stacking, with the key residues of α-glucosidase. Docking analysis revealed the importance of hydrazine carbothioamide moiety of compounds in the attachment of ligands with the crucial residues of α-glucosidase. The estimated pharmacokinetic, physicochemical, and drug likeness properties of compounds 3a-r reflects that these molecules have acceptable range of these properties.

Meldrum-Based-1H-1,2,3-Triazoles as Antidiabetic Agents: Synthesis, In Vitro α-Glucosidase Inhibition Activity, Molecular Docking Studies, and In Silico Approach

A series of novel alkyl derivatives (2-5a,b) and 1H-1,2,3-triazole analogues (7a-k) of Meldrum's acid were synthesized in a highly effective way by using "click" chemistry and screened for in vitro α-glucosidase inhibitory activity to examine their antidiabetic potential. ¹H NMR, ¹³C-NMR, and high-resolution electrospray ionization mass spectra (HR-ESI-MS) were used to analyze each of the newly synthesized compounds. Interestingly, these compounds demonstrated high to moderate α-glucosidase inhibitory potency having an IC₅₀ range of 4.63-80.21 μM. Among these derivatives, compound 7i showed extraordinary inhibitory activity and was discovered to be several times more potent than the parent compound Meldrum (1) and the standard drug acarbose. Later, molecular docking was performed to understand the binding mode and the binding strength of all the compounds with the target enzyme, which revealed that all compounds are well fitted in the active site of α-glucosidase. To further ascertain the structure of compounds, suitable X-ray single crystals of compounds 5a, 7a, and 7h were developed and studied. The current investigation has shown that combining 1H-1,2,3-triazole with the Meldrum moiety is beneficial. Furthermore, this is the first time that the aforementioned activity of these compounds has been reported.

Novel Pyrano[3,2-c]quinoline-1,2,3-triazole Hybrids as Potential Anti-Diabetic Agents: In Vitro α-Glucosidase Inhibition, Kinetic, and Molecular Dynamics Simulation

In this study, a novel series of pyrano[3,2-c]quinoline-1,2,3-triazole hybrids 8a-o were synthesized and evaluated against the α-glucosidase enzyme. All compounds showed significant in vitro inhibitory activity (IC₅₀ values of 1.19 ± 0.05 to 20.01 ± 0.02 μM) compared to the standard drug acarbose (IC₅₀ = 750.0 μM). Among them, 2-amino-4-(3-((1-benzyl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)-5-oxo-5,6-dihydro-4H-pyrano[3,2-c]quinoline-3-carbonitrile (compound 8k) demonstrated the best inhibitory effect toward α-glucosidase (IC₅₀ = 1.19 ± 0.05 μM) with a competitive pattern of inhibition. Since compound 8k was synthesized as a racemic mixture, molecular docking and dynamics simulations were performed on R- and S-enantiomers of compound 8k. Based on the molecular docking results, both R- and S-enantiomers of compound 8k displayed significant interactions with key residues including catalytic triad (Asp214, Glu276, and Asp349) in the enzyme active site. However, an in silico study indicated that S- and R-enantiomers were inversely located in the enzyme active site. The R-enantiomer formed a more stable complex with a higher binding affinity to the active site of α-glucosidase than that of the S- enantiomer. The benzyl ring in the most stable complex ((R)-compound 8k) was located in the bottom of the binding site and interacted with the enzyme active site, while the pyrano[3,2-c]quinoline moiety occupied the high solvent accessible entrance of the active site. Thus, the synthesized pyrano[3,2-c]quinoline-1,2,3-triazole hybrids seem to be promising scaffolds for the development of novel α-glucosidase inhibitors.

Synthetic α-glucosidase inhibitors as promising anti-diabetic agents: Recent developments and future challenges

Diabetes mellitus is one of the biggest challenges for the scientific community in the 21st century. It is a well-recognized multifactorial health problem contributes significantly to high mortality rates by causing serious health complications mainly related to cardiovascular diseases, kidney damage and neuropathy. The inhibition of α-glucosidase (enzyme that catalyses starch hydrolysis in the intestine) is an effective therapeutic approach for controlling hyperglycemia associated with type-2 diabetes. However, the presently approved drugs/inhibitors such as acarbose, miglitol and voglibose have several undesirable gastrointestinal side effects impeding their applications. Therefore, search for novel and more effective inhibitors with reduced side effects and less cost remains a fascinating area of research. In this context, a large variety of α-glucosidase inhibitors have been identified in recent years that demands attention from drug development community. This review is therefore an effort to summarize and highlight the promising α-glucosidase inhibitors especially those which are primarily based on aromatic heterocyclic scaffolds such as coumarin, imidazole, isatin, pyrimidine, quinazoline, triazine, thiazole etc, having improved safety and pharmacological profiles.

Discovery of new 1,4-disubstituted 1,2,3-triazoles: in silico ADME profiling, molecular docking and biological evaluation studies

In this work, eight new 1,2,3-triazoles (6a-h) were synthesized from acetylenes' "click" reaction with p-substituted azide derivatives. The structures of the compounds were characterized using standard analytical and spectroscopic methods (elemental analysis, FT-IR, ¹H(¹³C)NMR). The anticancer, antioxidant, α-amylase, ADME, molecular docking studies of synthesized triazoles were investigated. According to α -amylase enzyme inhibition results, all compounds except 6c (IC₅₀: 2299 μg/mL) were found to have a higher IC₅₀ value than the standard drug acarbose (IC₅₀: 891 μg/mL). Compound 6g (IC₅₀: 68 μg/mL) exhibited 13 times higher activity than standard acarbose. All compounds, except 6e, have been shown to have greater DPPH radical scavenging capabilities than BHT and β-carotene standards. According to ABTS radical scavenging studies, all compounds showed higher scavenging activity than ascorbic acid and Trolox. To determine the anticancer activity of the synthesized compounds, they were screened against the Hela cell line, and the results were compared with standard cisplatin (IC₅₀: 16.30 μg/mL). Compound 6a (IC₅₀: 49.03 μg/mL) was determined to have moderate activity relative to cisplatin. The compounds were examined comprehensively for ADME characteristics and did not violate any drug-likeness rule. ADME data showed that all physicochemical and pharmacological parameters of the compounds remained within defined limits as specified in Lipinski's rules (RO5) and put forth a high bioavailability profile. The molecular docking findings show that all molecules have a high affinity by exhibiting polar and apolar contact with essential residues in the binding pocket of α-amylase.Communicated by Ramaswamy H. Sarma.

Synthesis of new diphenyl urea-clubbed imine analogs and its Implications in diabetic management through in vitro and in silico approaches

Type II diabetes mellitus (T2DM) is a global health issue with high rate of prevalence. The inhibition of α-glucosidase enzyme has prime importance in the management of T2DM. This study was established to synthesize Schiff bases of 1,3-dipheny urea (3a-y) and to investigate their in vitro anti-diabetic capability via inhibiting α-glucosidase, a key player in the catabolism of carbohydrates. The structures of all compounds were confirmed through various techniques including, Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) and mass-spectrometry (MS) methods. Interestingly all these compounds displayed potent inhibition IC₅₀ values in range of 2.14-115 µM as compared to acarbose used as control. Additionally, all the compounds were docked at the active site of α-glucosidase to predict their mode of binding. The docking results indicates that Glu277 and Asn350 play important role in the stabilization of these compounds in the active site of enzyme. These molecules showed excellent predicted pharmacokinetics, physicochemical and drug-likeness profile. The anti-diabetic potential of these molecules signifies their medical importance and provide insights into prospective therapeutic options for the treatment of T2DM.

Chemistry and Therapeutic Aspect of Triazole: Insight into the Structure-activity Relationship

The triazole ring is a highly significant heterocycle that occurs naturally in many commodities and is a common feature in pharmaceuticals. Recently, heterocyclic compounds and their derivatives have been getting a lot of attention in medicinal chemistry because they have a lot of pharmacological and biological potential. For example, a lot of drugs have nitrogen-containing heterocyclic moieties. The triazole ring is often used as a bio-isostere of the oxadiazole nucleus. The oxygen atom in the oxadiazole nucleus is replaced by nitrogen in the triazole analogue. This article explores the pharmacological properties of the triazole moiety, including but not limited to antibacterial, analgesic, anticonvulsant, anthelmintic, anti-inflammatory, antitubercular, antimalarial, antioxidant, antiviral, and other properties. Additionally, we discuss the diverse multi- target pharmacological activities exhibited by triazole-based compounds. Based on a literature review, it is evident that triazole-based chemicals hold significant potential for various applications.

2,5-Bis(2,2,2-trifluoroethoxy)phenyl-tethered 1,3,4-Oxadiazoles Derivatives: Synthesis, In Silico Studies, and Biological Assessment as Potential Candidates for Anti-Cancer and Anti-Diabetic Agent

In the present work, a series of new 1-{5-[2,5-bis(2,2,2-trifluoroethoxy)phenyl]-1,3,4-oxadiazol-3-acetyl-2-aryl-2H/methyl derivatives were synthesized through a multistep reaction sequence. The compounds were synthesized by the condensation of various aldehydes and acetophenones with the laboratory-synthesized acid hydrazide, which afforded the Schiff's bases. Cyclization of the Schiff bases yielded 1,3,4-oxadiazole derivatives. By spectral analysis, the structures of the newly synthesized compounds were elucidated, and further, their anti-cancer and anti-diabetic properties were investigated. To examine the dynamic behavior of the candidates at the binding site of the protein, molecular docking experiments on the synthesized compounds were performed, followed by a molecular dynamic simulation. ADMET (chemical absorption, distribution, metabolism, excretion, and toxicity) prediction revealed that most of the synthesized compounds follow Lipinski's rule of 5. The results were further correlated with biological studies. Using a cytotoxic assay, the newly synthesized 1,3,4-Oxadiazoles were screened for their in vitro cytotoxic efficacy against the LN229 Glioblastoma cell line. From the cytotoxic assay, the compounds 5b, 5d, and 5m were taken for colony formation assay and tunnel assay have shown significant cell apoptosis by damaging the DNA of cancer cells. The in vivo studies using a genetically modified diabetic model, Drosophila melanogaster, indicated that compounds 5d and 5f have better anti-diabetic activity among the different synthesized compounds. These compounds lowered the glucose levels significantly in the tested model.

Biochemical and in silico inhibition of bovine and human carbonic anhydrase-II by 1H-1,2,3-triazole analogs

A series of 1H-1,2,3-triazole analogs (7a-7d and 9a-9s) were synthesized via "click" chemistry and evaluated for in vitro carbonic anhydrase-II (bovine and human) inhibitory activity. The synthesis of intermediates, 7a and 7c, was achieved by using (S)-(-)ethyl lactate as a starting material. These compounds (7a and 7c) underwent Suzuki-Miyaura cross-coupling reaction with different arylboronic acids in 1,4-dioxane, reflux at 90-120°C for 8 h using Pd(PPh₃)₄ as a catalyst (5 mol%), and K₂CO₃ (3.0 equiv)/K₂PO₄ (3.0 equiv) as a base to produce target 1H-1,2,3-triazole molecules (9a-9s) for a good yield of 67-86%. All the synthesized compounds were characterized through NMR spectroscopic techniques. Furthermore, all those compounds have shown significant inhibitory potential for both sources of carbonic anhydrase-II (CA-II). In the case of bCA-II, compounds 9i, 7d, 9h, 9o, 9g, and 9e showed potent activity with IC50 values in the range of 11.1-17.8 µM. Whereas for hCA-II, compounds 9i, 9c, 9o, and 9j showed great potential with IC50 values in the range of 10.9-18.5 µM. The preliminary structure-activity relationship indicates that the presence of the 1H-1,2,3-triazole moiety in those synthesized 1H-1,2,3-triazole analogs (7a-7d and 9a-9s) significantly contributes to the overall activity. However, several substitutions on this scaffold affect the activity to several folds. The selectivity index showed that compounds 9c, 9k, and 9p are selective inhibitors of hCA-II. Kinetics studies showed that these compounds inhibited both enzymes (bCA-II and hCA-II) in a competitive manner. Molecular docking indicates that all the active compounds fit well in the active site of CA-II. This study has explored the role of 1H-1,2,3-triazole-containing compounds in the inhibition of CA-II to combat CA-II-related disorders.

The 1,2,3-triazole 'all-in-one' ring system in drug discovery: a good bioisostere, a good pharmacophore, a good linker, and a versatile synthetic tool

INTRODUCTION

The 1,2,3-triazole ring occupies an important space in medicinal chemistry due to its unique structural properties, synthetic versatility and pharmacological potential making it a critical scaffold. Since it is readily available through click chemistry for creating compound collections against various diseases, it has become an emerging area of interest for medicinal chemists.

AREAS COVERED

This review article addresses the unique properties of the1,2,3-triazole nucleus as an intriguing ring system in drug discovery while focusing on the most recent medicinal chemistry strategies exploited for the design and development of 1,2,3-triazole analogs as inhibitors of various biological targets.

EXPERT OPINION

Evidently, the 1,2,3-triazole ring with unique structural features has enormous potential in drug design against various diseases as a pharmacophore, a bioisoster or a structural platform. The most recent evidence indicates that it may be more emerging in drug molecules in near future along with an increasing understanding of its prominent roles in drug structures. The synthetic feasibility and versatility of triazole chemistry make it certainly ideal for creating compound libraries for more constructive structure-activity relationship studies. However, more comparative and target-specific studies are needed to gain a deeper understanding of the roles of the 1,2,3-triazole ring in molecular recognition.[Figure: see text].

Fluorinated triazoles as privileged potential candidates in drug development—focusing on their biological and pharmaceutical properties

Fluorinated heterocycles have attracted extensive attention not only in organic synthesis but also in pharmaceutical and medicinal sciences due to their enhanced biological activities than their non-fluorinated counterparts. Triazole is a simple five-membered heterocycle with three nitrogen atoms found in both natural and synthetic molecules that impart a broad spectrum of biological properties including but not limited to anticancer, antiproliferative, inhibitory, antiviral, antibacterial, antifungal, antiallergic, and antioxidant properties. In addition, incorporation of fluorine into triazole and its derivatives has been reported to enhance their pharmacological activity, making them promising drug candidates. This mini-review explores the current developments of backbone-fluorinated triazoles and functionalized fluorinated triazoles with established biological activities and pharmacological properties.

Heterocyclic compounds as a magic bullet for diabetes mellitus: a review

Diabetes mellitus (DM) is a major metabolic disorder due to hyperglycemia, which is increasing all over the world. From the last two decades, the use of synthetic agents has risen due to their major involvement in curing of chronic diseases including DM. The core skeleton of drugs has been studied such as thiazolidinone, azole, chalcone, pyrrole and pyrimidine along with their derivatives. Diabetics assays have been performed in consideration of different enzymes such as α-glycosidase, α-amylase, and α-galactosidase against acarbose standard drug. The studied moieties were depicted in both models: in vivo as well as in vitro. Molecular docking of the studied compounds as antidiabetic molecules was performed with the help of Auto Dock and molecular operating environment (MOE) software. Amino acid residues Asp349, Arg312, Arg439, Asn241, Val303, Glu304, Phe158, His103, Lys422 and Thr207 that are present on the active sites of diabetic related enzymes showed interactions with ligand molecules. In this review data were organized for the synthesis of heterocyclic compounds through various routes along with their antidiabetic potential, and further studies such as pharmacokinetic and toxicology studies should be executed before going for clinical trials.

Diabetes mellitus (DM) is a major metabolic disorder due to hyperglycemia, which is increasing all over the world.

Discovery of new 2-phenyl-1H-benzo[d]imidazole core-based potent α-glucosidase inhibitors: Synthesis, kinetic study, molecular docking, and in vivo anti-hyperglycemic evaluation

In the present study, a series of 2-phenyl-1H-benzo[d]imidazole-based α-glucosidase inhibitors were synthesized and evaluated for their in vitro and in vivo anti-diabetic potential. Screening of an in-house library revealed a moderated α-glucosidase inhibitor, 6a with 3-(1H-benzo[d]imidazol-2-yl)aniline core, and then the structural optimization was performed to obtain more efficient derivatives. Most of these derivatives showed increased activity than 6a, and the most promising inhibitors were found to be compounds 15o and 22d with IC₅₀ values of 2.09 ± 0.04 and 0.71 ± 0.02 µM, respectively. Fluorescence quenching experiment confirmed the direct binding of compounds 15o and 22d with α-glucosidase. Kinetic study revealed that both compounds were non-competitive inhibitors, that was consistent with the result of molecular docking studies where they located at the allosteric site of the enzyme. Cell viability evaluation demonstrated the non-cytotoxicity of 15o and 22d against LO2 cells. Furthermore, the in vivo pharmacodynamic study revealed that compound 15o showed significant hypoglycemic activity and improved oral sucrose tolerance, comparable to the positive control acarbose.

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

Herein, a series of novel 1H-1,2,3-triazole and carboxylate derivatives of metronidazole (5a-i and 7a-e) were synthesized and evaluated for their antimicrobial activity in vitro. All the newly synthesized compounds were characterized by ¹H NMR, ¹³C NMR, HRMS, and ¹⁹F NMR (5b, 5c and 5h) spectroscopy wherever applicable. The structures of compounds 3, 5c and 7b were unambiguously confirmed by single crystal X-ray analysis diffraction method. Single crystal X-ray structure analysis supported the formation of the metronidazole derivatives. The antimicrobial (antifungal and antibacterial) activity of the prepared compounds was studied. All compounds (except 2 and 3) showed a potent inhibition rate of fungal growth as compared to control and metronidazole. The synthetic compounds also showed higher bacterial growth inhibiting effects compared to the activity of the parent compound. Amongst the tested compounds 5b, 5c, 5e, 7b and 7e displayed excellent potent antimicrobial activity. The current study has demonstrated the usefulness of the 1H-1,2,3-triazole moiety in the metronidazole skeleton.

Pentacyclic triterpene carboxylic acids derivatives integrated piperazine-amino acid complexes for α-glucosidase inhibition in vitro

Eighteen derivatives of pentacyclic triterpene carboxylic acids (Maslinic acid, Corosolic acid and Asiatic acid) have been prepared by coupling the piperazine complex of l-amino acids at the C-28 site of the parent compounds. The α-glucosidase inhibitory activities of the pristine derivatives were evaluated in vitro. The results indicated that the inhibitory activity of some compounds (15e IC₅₀ = 591 μM, 16e IC₅₀ = 423 μM) was closed to that of the reference acarbose (IC₅₀ = 347 μM) in ethanol-water system. In addition, compound 16e (IC₅₀ = 380 μM) showed superior inhibitory activity than acarbose (IC₅₀ = 493 μM) in the measurement system with DMSO as solvent. The comparison of two different solvent systems showed that the derivatives had better α-glucosidase inhibitory activity in the DMSO system than that of in ethanol-water system. Regrettably, all of the as-synthesized derivatives exhibited inferior α-glucosidase inhibitory activities than those of the parent compounds in both test solvent systems. Furthermore, the result of enzyme kinetics demonstrated that the inhibition mechanism of compound 16e was noncompetitive inhibition with the inhibition constant K_i = 552 μM.

Synthesis of New 1H-1,2,3-Triazole Analogs in Aqueous Medium via "Click" Chemistry: A Novel Class of Potential Carbonic Anhydrase-II Inhibitors

A series of novel 1H-1,2,3-triazole analogs (9a–j) were synthesized via “Click” chemistry and Suzuki–Miyaura cross-coupling reaction in aqueous medium. The compounds were evaluated for their carbonic anhydrase-II enzyme inhibitory activity in vitro. The synthesis of triazole 7a was accomplished using (S)-(-) ethyl lactate as a starting material. This compound (7a) underwent Suzuki–Miyaura cross-coupling reaction with different arylboronic acids in aqueous medium to afford the target molecules, 9a–j in good yields. All newly synthesized compounds were characterized by ¹H NMR, ¹³C NMR, FT-IR, HRMS, and where applicable ¹⁹F NMR spectroscopy (9b, 9e, 9h, and 9j). The new compounds have shown moderate inhibition potential against carbonic anhydrase-II enzyme. A preliminary structure-activity relationship suggested that the presence of polar group at the 1H-1,2,3-triazole substituted phenyl ring in these derivatives (9a–j) has contributed to the overall activity of these compounds. Furthermore, via molecular docking, it was deduced that the compounds exhibit inhibitory potential through direct binding with the active site residues of carbonic anhydrase-II enzyme. This study has unraveled a new series of triazole derivatives as good inhibitors against carbonic anhydrase-II.

Synthesis of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives as potential glucosidase inhibitors

BACKGROUND

A hybrid molecule of different biologically active substances can improve affinity and efficiency compared to a standard drug. Hence based on this fact, we predict that a combination of fluorine, oxadiazole, sulfur, etc., may enhance α-glucosidase inhibition activity compared to a standard drug.

METHODS

A series of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives (2a-2i) were synthesized and characterized using spectroscopic techniques such as ¹HNMR and LC-MS. In order to evaluate its bioactivity, in vitro α-amylase and α-glycosidase inhibitory activity were performed. In vivo study was carried using a genetic model, Drosophila melanogaster, for assessing the antihyperglycemic effects.

RESULTS

The compounds 2a-2i demonstrated α-amylase inhibitory activity in the range of IC₅₀ = 40.00-80.00 μg/ml as compare to standard acarbose (IC₅₀ = 34.71 μg/ml). Compounds 2a-2i demonstrated α-glucosidase inhibitory activity in the range of IC₅₀ = 46.01-81.65 μg/ml as compared to standard acarbose (IC₅₀ = 34.72 μg/ml). Docking studies on a target protein, N-terminal subunit of human Maltase-glucoamylase (PDB:2QMJ) was carried and the compounds were found to dock into the active site of the enzyme (Fig. 1). The predicted binding energies of the compounds were calculated. The in vitro studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. Whereas in vivo study indicates that 2b, 2g, and 2i could lower glucose levels in the Drosophila, but then 17-30% reduced capacity than acarbose and may be overcome by adjusting their dosage.

CONCLUSIONS

The in vitro and in vivo studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. This study has recognized that compounds like 2b, 2g, and 2i may be considered potential candidates for further developing a novel class of antidiabetic agents.

Triazole analogues as potential pharmacological agents: a brief review

Background

A large number of studies have recently reported that, because of their significant biological and pharmacological properties, heterocyclic compounds and their derivatives have attracted a strong interest in medicinal chemistry. The triazole nucleus is one of the most important heterocycles which has a feature of natural products as well as medicinal agents. Heterocyclic nitrogen is abundantly present in most medicinal compounds. The derivatization of triazole ring is based on the phenomenon of bio-isosteres in which substituted the oxygen atom of oxadiazole nucleus with nitrogen triazole analogue.

Main text

This review focuses on recent synthetic procedure of triazole moiety, which comprises of various pharmacological activities such as antimicrobial, anticonvulsant, anti-inflammatory, analgesic, antitubercular, anthelmintic, antioxidant, antimalarial, antiviral, etc..

Conclusion

This review highlights the current status of triazole compounds as different multi-target pharmacological activities. From the literature survey, triazole is the most widely used compound in different potential activities.

Synthesis, in vitro evaluation, and molecular docking studies of novel hydrazineylideneindolinone linked to phenoxymethyl-1,2,3-triazole derivatives as potential α-glucosidase inhibitors

In this work, a novel series of hydrazineylideneindolinone linked to phenoxymethyl-1,2,3-triazole derivatives were designed, synthesized, and evaluated for their anti-α-glucosidase activity due to an urgent need to develop effective anti-diabetic agents. Among tested 15 compounds, 8 derivatives (9a, 9b, 9c, 9d, 9e, 9f, 9h, and 9o) demonstrated superior potency compared to that of positive control, acarbose. Particularly, compound 9d possessed the best anti-α-glucosidase activity with around a 46-fold improvement in the inhibitory activity. Additionally, 9d showed a competitive type of inhibition in the kinetic study and the molecular docking study demonstrated that it well occupied the binding pocket of the catalytic center through desired interactions with residues, correlating to the experimental results.

Synthesis and studies of thiazolidinedione-isatin hybrids as α-glucosidase inhibitors for management of diabetes

Aim: Keeping in view the side effects associated with clinically used α-glucosidase inhibitors, novel thiazolidinedione-isatin hybrids were synthesized and evaluated by in vitro, in vivo and in silico procedures. Materials & methods: Biological evaluation, cytotoxicity assessment, molecular docking, binding free energy calculations and molecular dynamics studies were performed for hybrids. Results: The most potent inhibitor A-10 (IC₅₀ = 24.73 ± 0.93 μM) was competitive in manner and observed as non-cytotoxic. A-10 possessed higher efficacy than the standard drug (acarbose) during in vivo biological testing. Conclusion: The enzyme inhibitory potential and safety profile of synthetic molecules was recognized after in vitro, in vivo, in silico and cytotoxicity studies. Further structural optimization of A-10 can offer potential hit molecules suitable for future investigations.

Therapeutic potential of N4-substituted thiosemicarbazones as new urease inhibitors: Biochemical and in silico approach

Urease enzyme plays a key role in pathogenesis of gastritis and peptic ulcers. Its inhibition averts our bodies from many disorders including formation of urinary calculi. In agriculture, the high urease content causes severe environmental and hence economic problems. Due to deficiency of effective and safer drugs to tackle the aforementioned disorders, the quest for new scaffolds becomes mandatory in the field of medicinal chemistry. In this regard, we herein report a new series of N⁴-substituted thiosemicarbazones 3a-v as potential candidates for urease inhibition. These new N⁴-substituted thiosemicarbazones 3a-v of distant chemical scaffolds were characterized by advanced spectroscopic techniques, such as FTIR, ¹HNMR, ¹³CNMR, ESI-MS and in the case of compound 3g by single crystal X-ray analysis. The compounds were evaluated for their urease inhibitory potential. All newly synthesized compounds showed significant urease inhibitions with IC₅₀ values in range of 2.7 ± 0.320-109.2 ± 3.217 μM. Molecular docking studies were used for interactions pattern and structure-activity relationship for all compounds, which demonstrated excellent binding interactions with the active site residues, such as hydrogen bonding, π-π interactions, π-H and nickel atom coordination.

Design, synthesis, antibacterial evaluation, molecular docking and computational study of 4-alkoxy/aryloxyphenyl cyclopropyl methane oxime derivatives

A series of new 4-alkoxy/aryloxyphenyl cyclopropyl methane oxime derivatives 2(a-k) were synthesized and fully characterized by FT-IR, 1H-NMR, 13C-NMR and Mass spectrometry techniques. All the synthesized compounds 2(a-k) were assayed for in vitro antibacterial activity against a selected bacterial strain and the compound (2 h) and (2k) exerted excellent activity against Staphylococcus aureus, Escherichia coli and Salmonella typhi strains. The potency of inhibitors and possible interaction mechanism of synthetic oxime (2k) with 1GQN enzyme on Salmonella typhi was explored by molecular docking method. Amongst the all synthesized compounds, the quantum chemical calculations were done for Cyclopropyl(4-(pyridin-3-ylmethoxy)phenyl)methanone oxime (2k). The first hyperpolarizability calculation performed in different solvent such as CHCl₃, CH₂Cl₂ and DMSO and compared to the reference compound urea. In addition, natural bond orbital analysis (NBO), local reactivity descriptors, thermodynamic properties, Mulliken charges, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were explored using theoretical calculations.

Structural characterization and QSAR modeling of 1,2,4-triazole derivatives as α-glucosidase inhibitors

In order to identify potential new drugs classified as alpha-Glucosidase inhibitors (AGIs), we used quantum chemical descriptors and QSAR modeling to predict the biological activity of triazole derivatives as AGIs.

The study on the interactions of two 1,2,3-triazoles with several biological macromolecules by multiple spectroscopic methodologies and molecular docking

1-(4-chlorophenyl)-5-phenyl-1H-1,2,3-triazole (CPTC) and 5-(3-chlorophenyl) -1-phenyl-1H-1,2,3-triazole (PCTA) are two new derivatives of 1,2,3-triazole. Their structural and spectral properties were characterized by density functional theory calculations (DFT). The binding properties of CPTC or PCTA with several typical biomacromolecules such as human serum albumin (HSA), bovine hemoglobin (BHb), human immunoglobulin (HIgG) or DNA were investigated by molecular docking and multiple spectroscopic methodologies. The different parameters including binding constants and thermodynamic parameters for CPTC/PCTA-HSA/BHb/HIgG/DNA systems were obtained based on various fluorescence enhancement or quenching mechanisms. The results of binding constants indicated that there were the strong interactions between two triazoles and four biological macromolecules due to the higher order of magnitude between 10³ and 10⁵. The values of thermodynamic parameters revealed that the binding forces for these systems are mainly hydrophobic interactions, electrostatic force, or hydrogen bond, respectively, which are in agreement with the results of molecular docking to a certain extent. Moreover, the information from synchronous, 3D fluorescence and UV-Vis spectroscopies proved that two compounds CPTC and PCTA could affect the microenvironment of amino acids residues of three kinds of proteins. Based on the above experimental results, a comparison of the interaction mechanisms for CPTC/PCTA-proteins/DNA systems have been performed in view of their different molecular structures, which is beneficial for the further research in order to design them as the novel drugs.

Antimicrobial Screening, in Silico Studies and QSAR of Chalcone-based 1,4-disubstituted 1,2,3-triazole Hybrids

The in vitro antimicrobial properties of some chalcones (1A-1C: ) and chalcone tethred 1,4-disubstituted 1,2,3-triazoles (2A-2U: ) towards different microbial strains viz. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger and Candida albicans are reported. Compounds 2G: and 2U: exhibited better potency than the standard Fluconazole with MIC values of 0.0063 µmol/mL and 0.0068 µmol/mL, respectively. Furthermore, molecular docking was performed to investigate the binding modes of two potent compounds 2Q: and 2G: with E. coli topoisomerase II DNA gyrase B and C. albicans lanosterol 14α-demethylase, respectively. Based on these results, a statistically significant quantitative structure activity relationship (QSAR) model was successfully summarized for antibacterial activity against B. subtilis.