Synthesis, lipophilicity and biological evaluation of indole-containing derivatives of 1,3,4-thiadiazole and 1,2, 4-triazole

New tetrazolopyrrolidine-1,2,3-triazole analogues as potent anticancer agents: design, synthesis and molecular docking studies

1,2,3-Triazole and tetrazole derivatives bearing pyrrolidines are found to exhibit notable biological activity and have become useful scaffolds in medicinal chemistry for application in lead discovery and optimization. We report design, synthesis and molecular docking studies of tetrazolyl-1,2,3-triazole derivatives (7a-i) bearing pyrrolidine moiety and evaluating their anticancer activity against four cancer cell lines viz. Hela, MCF-7, HCT-116 and HepG2. The structures of the new compounds were ascertained by spectral means IR, NMR: 1H &13C and Mass spectrum. From the studies compounds7a and 7i exhibited significant anticancer activity against the Hela cell line with IC50 = 0.32 ± 1.00, 1.80 ± 0.22 μM when compared to reference drug Doxorubicin (IC50 = 2.34 ± 0.11 μM), whereas 7h, 7i, and 7b were found to be active against MCF-7, HCT-116 and HepG2 cell lines with IC50 = 3.20 ± 1.40, 1.38 ± 0.06 and 0.97 ± 0.12 μM respectively. Notably 7a exhibited highest conventional hydrogen bondings TyrA:40, SerA:17, LysA:117, AlaA:146, Tyr218 with 3HB4and SerA:17, LysA:117, AlaA:146, TyrA:40 with 6IBZ and docking energy - 10.85, - 8.21 kcal/mol respectively. These compounds were further evaluated for their ADMET and physicochemical properties by using SwissADME. The results of the in vitro and in silico studies suggest that the tetrazole incorporated pyrrolidine-triazoles may possess the ideal structural requirements for further developing new anticancer agents.

Steroid-triazole conjugates: A brief overview of synthesis and their application as anticancer agents

Steroids are biomolecules that play pivotal roles in various physiological and drug discovery processes. Abundant research has been fuelled towards steroid-heterocycles conjugates over the last few decades as potential therapeutic agents against various diseases especially as anticancer agents. In this context various steroid-triazole conjugates have been synthesized and studied for their anticancer potential against various cancer cell lines. A thorough search of the literatures revealed that a concise review pertaining the present topic is not compiled. Therefore, in thus review we summarize the synthesis, anticancer activity against various cancer cell lines and structure activity relationship (SAR) of various steroid-triazole conjugates. This review can lay down the path towards the development of various steroid-heterocycles conjugates with lesser side effects and profound efficacy.

NRF2 Activation by Nitrogen Heterocycles: A Review

Several nitrogen heterocyclic analogues have been applied to clinical practice, and about 75% of drugs approved by the FDA contain at least a heterocyclic moiety. Thus, nitrogen heterocycles are beneficial scaffolds that occupy a central position in the development of new drugs. The fact that certain nitrogen heterocyclic compounds significantly activate the NRF2/ARE signaling pathway and upregulate the expression of NRF2-dependent genes, especially HO-1 and NQO1, underscores the need to study the roles and pharmacological effects of N-based heterocyclic moieties in NRF2 activation. Furthermore, nitrogen heterocycles exhibit significant antioxidant and anti-inflammatory activities. NRF2-activating molecules have been of tremendous research interest in recent times due to their therapeutic roles in neuroinflammation and oxidative stress-mediated diseases. A comprehensive review of the NRF2-inducing activities of N-based heterocycles and their derivatives will broaden their therapeutic prospects in a wide range of diseases. Thus, the present review, as the first of its kind, provides an overview of the roles and effects of nitrogen heterocyclic moieties in the activation of the NRF2 signaling pathway underpinning their antioxidant and anti-inflammatory actions in several diseases, their pharmacological properties and structural-activity relationship are also discussed with the aim of making new discoveries that will stimulate innovative research in this area.

1,3,4-Thiadiazole Scaffold: As Anti-Epileptic Agents

A wide range of biological activities is exhibited by 1,3,4-thiadiazole moiety such as antidiabetic, anticancer, anti-inflammatory, anticonvulsant, antiviral, antihypertensive, and antimicrobial. To date, drugs such as butazolamide, and acetazolamide. Several modifications have been done in the 1,3,4-thiadiazole moiety which showed good potency as anticonvulsant agents which are highly effective and have less toxicity. After in-depth literature survey in this review, we have compiled various derivatives of 1,3,4-thiadiazole scaffold as anticonvulsant agents.

Synthesis and biological evaluation of 1,2,4-triazolidine-3-thiones as potent acetylcholinesterase inhibitors: in vitro and in silico analysis through kinetics, chemoinformatics and computational approaches

We have designed and synthesized a novel acidic ionic liquid and explored its catalytic efficiency for the synthesis of 1,2,4-triazolidine-3-thione derivatives. A simple reaction between aldehydes and thiosemicarbazide for short time in 60:40 v/v water/ethanol at room temperature offers target 1,2,4-triazolidine-3-thione derivatives. The formation of target compounds is confirmed by NMR, IR and ESI-MS analysis. Pleasingly, synthesized compounds show noteworthy acetylcholinesterase (AChE) inhibitory activity with much lower IC₅₀ values 0.0269 ± 0.0021-1.1725 ± 0.0112 μM than standard Neostigmine methylsulphate. In addition, synthesized 1,2,4-triazolidine-3-thiones exhibits significant free radical scavenging activity as compared to standard vitamin C. The studies on validation of Lipinski's rule through chemoinformatics properties and molecular docking analysis are in support of in vitro analysis. Therefore, overall present study illustrates synthesis of some new 1,2,4-triazolidines-3-thiones which can serve as a template for drug designing such as AChE inhibitors. Herein, we proposed ionic liquid-catalyzed ease of synthetic approach for medicinally important 1,2,4-triazolidine-3-thiones and their bio-evaluations.

Synthesis of Some Novel Thiadiazole Derivative Compounds and Screening Their Antidepressant-Like Activities

Novel thiadiazole derivatives were synthesized through the reaction of acetylated 2-aminothiadiazole and piperazine derivatives. The chemical structures of the compounds were clarified by Infrared Spectroscopy (IR), ¹H Nuclear Magnetic Resonance Spectroscopy (¹H-NMR), ¹³C Nuclear Magnetic Resonance Spectroscopy (¹³C-NMR) and Electronspray Ionisation Mass Spectroscopy (ESI-MS) spectroscopic methods. Antidepressant-like activities were evaluated by the tail-suspension (TST) and modified forced swimming (MFST) methods. Besides, possible influence of the test compounds on motor activities of the animals were examined by activity cage tests. In the TST, administration of the compounds 2c, 2d, 2e, 2f, 2g and 2h significantly decreased the immobility time of mice regarding the control values. Further, in the MFST, the same compounds reduced the total number of immobility behaviors while increasing swimming performance. However, no change was observed in the total number of climbing behaviors. These data suggested that compounds 2c, 2d, 2e, 2f, 2g and 2h possess notable antidepressant-like activities. Reference drug fluoxetine (10 mg/kg) was also exhibited its antidepressant activity, as expected. No significant difference was seen between the locomotor activity values of the test groups signifying that observed antidepressant-like activities are specific. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME) properties for the obtained compounds were performed and obtained data supported the antidepressant-like potential of these novel thiadiazole derivatives.

Synthesis of Novel 2,5-Disubstituted-1,3,4-thiadiazoles Clubbed 1,2,4-Triazole, 1,3,4-Thiadiazole, 1,3,4-Oxadiazole and/or Schiff Base as Potential Antimicrobial and Antiproliferative Agents

In the present study, a new series of 2,5-disubstituted-1,3,4-thiadiazole tethered 1,2,4-triazole, 1,3,4-thiadiazole, 1,3,4-oxadiazole and Schiff base derivatives were synthesized and characterized by IR, ¹H-NMR, ¹³C-NMR, MS and elemental analyses. All compounds were screened for their antibacterial, antifungal and antiproliferative activity. Some of the synthesized derivatives have displayed promising biological activity.

Triazoles: a valuable insight into recent developments and biological activities

In recent years, heterocyclic compounds, analogs, and derivatives have attracted strong interest due to their useful biological and pharmacological properties. The small and simple triazole nucleus is present in compounds aimed at evaluating new entities that possess anti-microbial, anti-tumor, antitubercular, anti-convulsant, anti-depressant, antimalarial, and anti-inflammatory activities. Triazoles display a broad range of biological activities and are found in many potent, biologically active compounds, such as trazodone (antidepressant drug), rizatriptan (antimigrane drug), hexaconazole (antifungal drug) and alprazolam (hyptonic, sedative and tranquilizer drug). So far, modifications of the triazole ring have proven highly effective with improved potency and lesser toxicity. The present review highlights the recently synthesized triazoles possessing important biological activities.

New thiosemicarbazides and 1,2,4-triazolethiones derived from 2-(ethylsulfanyl) benzohydrazide as potent antioxidants

New thiosemicarbazide derivatives 2–6 were synthesised by reacting 2-(ethylsulfanyl)benzohydrazide with various aryl isothiocyanates. The cyclisation of compounds 2–6 under reflux conditions in a basic medium (aqueous NaOH, 4 N) yielded compounds 7–11 that contain a 1,2,4-triazole ring. All of the synthesised compounds were screened for their antioxidant activities. Compounds 2, 3, and 7 showed better radical scavenging in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, with IC₅₀ values of 1.08, 0.22, and 0.74 µg/mL, respectively, compared to gallic acid (IC₅₀, 1.2 µg/mL). Compound 3 also showed superior results in a ferric reducing antioxidant power (FRAP) assay (3054 µM/100 g) compared to those of ascorbic acid (1207 µM/100 g).

Synthetic methods, chemistry, and the anticonvulsant activity of thiadiazoles

The chemistry of heterocyclic compounds has been an interesting field of study for a long time. Heterocyclic nucleus 1,3,4-thiadiazole constitutes an important class of compounds for new drug development. The synthesis of novel thiadiazole derivatives and investigation of their chemical and biological behavior have gained more importance in recent decades. The search for antiepileptic compounds with more selective activity and lower toxicity continues to be an active area of intensive investigation in medicinal chemistry. During the recent years, there has been intense investigation of different classes of thiadiazole compounds, many of which possess extensive pharmacological activities, namely, antimicrobial activity, anticonvulsant, antifungal antidiabetic, anti-inflammatory, antioxidant, and antituberculosis activities, and so forth. The resistance towards available drugs is rapidly becoming a major worldwide problem. The need to design new compounds to deal with this resistance has become one of the most important areas of research today. Thiadiazole is a versatile moiety that exhibits a wide variety of biological activities. Thiadiazole moiety acts as "hydrogen binding domain" and "two-electron donor system." It also acts as a constrained pharmacophore. On the basis of the reported literature, we study here thiadiazole compounds and their synthetic methods chemistry and anticonvulsant activity.

Synthesis and Antimicrobial Activity of Some [1,2,4]-Triazole Derivatives

A series of novel [1,2,4]-triazolo piperidine (8), [1,2,4]-triazolo piperazine (9a-c), [1,2,4]-triazolo phenylether (10a-e), and [1,2,4]-triazolo aniline (11a-c) derivatives have been synthesized. The chemical structures of the newly synthesized compounds were characterized by IR,1H NMR,13C NMR, and LCMS. The newly synthesized compounds were screened for antimicrobial activity. Among all the compounds tested,11b(R4=4-MeO–) showed the highest activity againstStaphylococcus aureusandEscherichia coli, and9a(R1andR2=Cl) showed the highest activity againstPseudomonas aeruginosa.

Synthesis and Antidepressant Activity of Some New 5-(1H-Indol-3-yl)-3-(substituted aryl)-4,5-dihydroisoxazoline Derivatives

The present study refers to the synthesis of new antidepressant candidates using the indole scaffold. In an attempt to identify potential lead antidepressant agents, a number of indole molecules, incorporating isoxazoline, were synthesized by microwave-assisted synthesis. The antidepressant activity of the synthesized compounds(3a–3n)was evaluated by forced swim test in mice and their locomotor activity was assessed using actophotometry. The present paper showed significant antidepressant activity for all compounds of the series and no significant change in locomotor activity of mice. Compounds3dand3jwere found to be potent molecules of this series, when compared with the reference drugs imipramine and fluoxetine. It clearly demonstrated that replacement of aromatic core by appropriate heterocycles such as pyridine and pyrrole on the 5-(1H-Indol-3-yl)-3-(Phenyl)-4,5-dihydroisoxazoline(3a)would generate more potent derivatives. Thus, these compounds can serve as potential leads for further antidepressant studies.