1H-1,2,3-Triazolyl-substituted 1,3,4-oxadiazole derivatives containing structural features of ibuprofen/naproxen: Their synthesis and antibacterial evaluation

Design, classification, and adverse effects of NSAIDs: A review on recent advancements

Inflammation is a hallmark of many diseases, including cancer, neurodegenerative diseases like Alzheimer's, type II diabetes, rheumatoid arthritis, and asthma. Nonsteroidal anti-inflammatory drugs (NSAIDs) have been a cornerstone in the management of various inflammatory, pain, and fever-related conditions. As a result, NSAIDs have found their applications in new therapeutic areas. NSAIDs are known to act by inhibiting the cyclooxygenase (COX) pathway. In recent years, new strategies have been proposed to counter inflammation and develop safer COX inhibitors. This review discusses the design of new COX inhibitors, the derivatization of conventional NSAIDs, and their biological applications. The review also presents an integrated classification of NSAIDs incorporating both traditional chemical-based and function-based approaches, including a brief overview of the NSAIDs of natural origins. Additionally, the review addresses adverse effects associated with different NSAIDs, including effects associated with cardiovascular, renal, and hepatic complications emphasizing the need for the development of new and safer COX inhibitors.

Polyaromatic Hydrocarbon (PAH)-Based Aza-POPOPs: Synthesis, Photophysical Studies, and Nitroanalyte Sensing Abilities

1,4-Bis(5-phenyl-2-oxazolyl)benzene (POPOP) is a common scintillation fluorescent laser dye. In this manuscript, the synthesis of 2-Ar-5-(4-(4-Ar'-1H-1,2,3-triazol-1-yl)phenyl)-1,3,4-oxadiazoles (Ar, Ar' = Ph, naphtalenyl-2, pyrenyl-1, triphenilenyl-2), as PAH-based aza-analogues of POPOP, by means of Cu-catalyzed click reaction between 2-(4-azidophenyl)-5-Ar-1,3,4-oxadiazole and terminal ethynyl-substituted PAHs is reported. An investigation of the photophysical properties of the obtained products was carried out, and their sensory response to nitroanalytes was evaluated. In the case of pyrenyl-1-substituted aza-POPOP, dramatic fluorescence quenching by nitroanalytes was observed.

Click chemistry inspired syntheses of new amide linked 1,2,3-triazoles from naphthols: biological evaluation and in silico computational study

In search of new active molecules, a small focused library of new 1,2,3-triazoles derived from naphthols were efficiently prepared via the click chemistry approach. The synthesized triazole derivatives were evaluated for their antifungal, antioxidant and antitubercular activities. Furthermore, to rationalize the observed biological activity data, the molecular docking study has also been carried out against the active site of cytochrome P450 lanosterol 14α-demethylase of C. albicans to understand the binding affinity and binding interactions of enzyme and synthesized derivatives, which revealed a significant correlation between the binding score and biological activity for these compounds. The results of the in vitro and In Silico study suggest that the 1,2,3-triazole derivatives may possess the ideal structural requirements for the further development of novel therapeutic agents.

1,3,4-oxadiazole derivatives as potential antimicrobial agents

Due to the emergence of drug-resistant microbial strains, different research groups are continuously developing novel drug molecules against already exploited and unexploited targets. 1,3,4-Oxadiazole derivatives exhibited noteworthy antimicrobial activities. The presence of 1,3,4-oxadiazole moiety in antimicrobial agents can modify their polarity and flexibility, which significantly improves biological activities due to various bonded and non-bonded interactions viz. hydrogen bond, steric, electrostatic, and hydrophobic with target sites. The present review elaborates the therapeutic targets and mode of interaction of 1,3,4-oxadiazoles as antimicrobial agents. 1,3,4-oxadiazole derivatives target enoyl reductase (InhA), 14α-demethylase in the mycobacterial cell; GlcN-6-P synthase, thymidylate synthase, peptide deformylase, RNA polymerase, dehydrosqualene synthase in bacterial strains; ergosterol biosynthesis pathway, P450-14α demethylase, protein-N-myristoyltransferase in fungal strains; FtsZ protein, interfere with purine and functional protein synthesis in plant bacteria. The present review also summarizes the effect of different moieties and functional groups on the antimicrobial activity of 1,3,4-oxadiazole derivatives.

A minireview of 1,2,3-triazole hybrids with O-heterocycles as leads in medicinal chemistry

Over the past few decades, the dynamic progress in the synthesis and screening of heterocyclic compounds against various targets has made a significant contribution in the field of medicinal chemistry. Among the wide array of heterocyclic compounds, triazole moiety has attracted the attention of researchers owing to its vast therapeutic potential and easy preparation via copper and ruthenium-catalyzed azide-alkyne cycloaddition reactions. Triazole skeletons are found as major structural components in a different class of drugs possessing diverse pharmacological profiles including anti-cancer, anti-bacterial, anti-fungal, anti-viral, anti-oxidant, anti-inflammatory, anti-diabetic, anti-tubercular, and anti-depressant among various others. Furthermore, in the past few years, a significantly large number of triazole hybrids were synthesized with various heterocyclic moieties in order to gain the added advantage of the improved pharmacological profile, overcoming the multiple drug resistance and reduced toxicity from molecular hybridization. Among these synthesized triazole hybrids, many compounds are available commercially and used for treating different infections/disorders like tazobactam and cefatrizine as potent anti-bacterial agents while isavuconazole and ravuconazole as anti-fungal activities to name a few. In this review, we will summarize the biological activities of various 1,2,3-triazole hybrids with copious oxygen-containing heterocycles as lead compounds in medicinal chemistry. This review will be very helpful for researchers working in the field of molecular modeling, drug design and development, and medicinal chemistry.

Antimicrobial Activity of 1,3,4-Oxadiazole Derivatives

The worldwide development of antimicrobial resistance forces scientists to search for new compounds to which microbes would be sensitive. Many new structures contain the 1,3,4-oxadiazole ring, which have shown various antimicrobial activity, e.g., antibacterial, antitubercular, antifungal, antiprotozoal and antiviral. In many publications, the activity of new compounds exceeds the activity of already known antibiotics and other antimicrobial agents, so their potential as new drugs is very promising. The review of active antimicrobial 1,3,4-oxadiazole derivatives is based on the literature from 2015 to 2021.

Anticancer and Antimicrobial Activities of Naproxen and Naproxen Derivatives

This review explains the effects of naproxen and the naproxen moiety in important biological activities. Naproxen, 2-(6-methoxynaphthalen-2-yl)propionic acid, is one of the most utilized propionic acid derivatives to the cure of many injuries or pains. Naproxen is a non-steroidal antiinflammatory drug (NSAID), which is generally used among the NSAIDs. Even though it has gastrointestinal side effects, naproxen has been safely used for many years because of the good cardiovascular sight. In the past years, except for anti-inflammatory effects, other pharmacological activities of naproxen, especially anticancer and antimicrobial activities, gain the attention of researchers. Naproxen shows its activity by inhibiting the COX-2 enzyme. There is significant interest in the possibility that COX-2 inhibitors might retard or prevent the development of various cancer types, which is often characterized by COX-2 expression. The activities of both naproxen and new molecules derived from naproxen were frequently investigated.

2,4-Diketo esters: Crucial intermediates for drug discovery

Convenient structures such as 2,4-diketo esters have been widely used as an effective pattern in medicinal chemistry and pharmacology for drug discovery. 2,4-Diketonate is a common scaffold that can be found in many biologically active and naturally occurring compounds. Also, many 2,4-diketo ester derivatives have been prepared due to their suitable synthesis. These synthetic drugs and natural products have shown numerous interesting biological properties with clinical potential as a cure for the broad specter of diseases. This review aims to highlight the important evidence of 2,4-diketo esters as a privileged scaffold in medicinal chemistry and pharmacology. Herein, numerous aspects of 2,4-diketo esters will be summarized, including synthesis and isolation of their derivatives, development of novel synthetic methodologies, the evaluation of their biological properties as well as the mechanisms of action of the diketo ester derivates. This paperwork is expected to be a comprehensive, trustworthy, and critical review of the 2,4-diketo ester intermediate to the chemistry community.

Evaluation and Docking Study of Pyrazine Containing 1, 3, 4-Oxadiazoles Clubbed with Substituted Azetidin-2-one: A New Class of Potential Antimicrobial and Antitubercular

BACKGROUND

Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the main killers of people all over the world. The major hurdles with existing therapy are the lengthy regimen and appearance of multi drug resistant (MDR) and extensively drug resistant (XDR) strains of M.tuberculosis.

AIMS

The present work was aimed to synthesize and determine antitubercular and antimicrobial potential of some novel 3-chloro-4-aryl-1-[4-(5-pyrazin-2-yl[1,3,4]oxadiazole-2-ylmethoxy)-phenyl]-azetidin-2-one derivatives 7: (A: -H: ) from pyrazinoic acid as precursor, which is a well-established antitubercular agent. Here we report the synthesis of a new class of heterocyclic molecules in which pyrazine, 1, 3, 4-oxadiazole and azetidinone moieties were present in one frame work.

METHODS

Pyrazinoic acid (1: ) was esterified first (2: ) followed by amination to produce hydrazide (3: ) which was refluxed with POCl3 to obtain 2-chloromethyl-5pyrazino-1, 3, 4-oxadiazole (4: ). This was then further reacted with 4-amino phenol to obtain 4-[5-pyrazino-1, 3, 4-oxadiazol-2-yl-methoxy]-phenyl amine (5: ) which on condensation with various aromatic aldehydes afforded a series Schiff's bases 6(A-H): . Dehydrative annulations of 6(A-H): in the presence of chloroacetyl chloride and triethylamine yielded 3-chloro-4-aryl-1-[4-(5-pyrazin-2-yl-[1, 3, 4]oxadiazole-2-ylmethoxy)-phenyl]-azetidin-2-one derivatives 7(A-H): . Antibacterial, antifungal and antitubercular potential of all the synthesized compounds were assessed. Docking study was performed using the software VLife Engine tools of Vlifemds 4.6 on the protein lumazine synthase of M. tuberculosis (PDB entry code 2C92).

RESULTS

The present studies demonstrated that synthesized oxadiazole derivatives have good antimicrobial activity against the various microorganisms. Among the synthesized derivative, 7B: and 7G: were found to be prominent compounds which have potential antibacterial, antifungal and antitubercular activity (with MIC 3.12 µg/ml and high dock score ranging from -59.0 to -54.0) against Mycobacterium tuberculosis.

CONCLUSIONS

Derivatives 7B: and 7G: would be effective lead candidates for tuberculosis therapy.

Synthesis, anticancer evaluation and molecular docking studies of new benzimidazole- 1,3,4-oxadiazole derivatives as human topoisomerase types I poison

In this study, some benzimidazole-oxadiazole derivatives were synthesised and tested for their in vitro anticancer activities on five cancer cell lines, including HeLa, MCF7, A549, HepG2 and C6. Their structures were elucidated by IR, ¹H-NMR, ¹³C-NMR, 2 D-NMR and HRMS spectroscopic methods. Among all screened compounds; 5a, 5b, 5d, 5e, 5k, 5l, 5n and 5o exhibited potent selective cytotoxic activities against various tested cancer cell lines. Especially, compounds 5l and 5n exhibited the most antiproliferative activity than Hoechst 33342 and doxorubicin against HeLa cell line, with IC₅₀ of 0.224 ± 0.011 µM and 0.205 ± 0.010 µM, respectively. Furthermore, these potent lead cytotoxic agents were evaluated in terms of their inhibition potency against Topoisomerase I and it was determined that selected compounds inhibited the Topoisomerase I. Docking studies were performed and probable interactions in the DNA-Topo I enzyme complex was determined.

New N-phenylacetamide-linked 1,2,3-triazole-tethered coumarin conjugates: Synthesis, bioevaluation, and molecular docking study

A series of new 1,2,3-triazole-tethered coumarin conjugates linked by N-phenylacetamide was efficiently synthesized via the click chemistry approach in excellent yields. The synthesized conjugates were evaluated for their in vitro antifungal and antioxidant activities. Antifungal activity determination was carried out against fungal strains such as Candida albicans, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger and Cryptococcus neoformans. Compounds 7b, 7d, 7e, 8b and 8e displayed higher potency than the standard drug miconazole, with lower minimum inhibitory concentration values. Also, compound 7a exhibited potential radical scavenging activity as compared with the standard antioxidant butylated hydroxytoluene. In addition, a molecular docking study of the newly synthesized compounds was carried out, and the results showed a good binding mode at the active site of the fungal (C. albicans) P450 cytochrome lanosterol 14α-demethylase enzyme. Furthermore, the synthesized compounds were also tested for ADME properties, and they demonstrated potential as good candidates for oral drugs.

Microwave-assisted synthesis, biological evaluation and molecular docking studies of new coumarin-based 1,2,3-triazoles

Coumarin-based 1,4-disubstituted 1,2,3-triazole derivatives were synthesized using a highly efficient, eco-friendly protocol via a copper(i)-catalyzed click reaction between various substituted arylazides and terminal alkynes. The synthetic route was easy to access and gave excellent yields under microwave irradiation conditions compared to the conventional heating route. The structures of all the compounds were characterized by IR, 1H NMR, 13C NMR spectroscopy and mass spectrometry. All the synthesized compounds were screened for their in vitro antimicrobial, antioxidant and anti-inflammatory activities; among all compounds, 8a, 8j, 8k and 8l exhibited better results with respect to standard drugs. Furthermore, molecular docking studies have been carried out with PDB IDs 2VCX (anti-inflammatory), 3VXI (antioxidant), 4GEE (antimicrobial) and 2XFH (antifungal) using the Glide module of the Schrödinger suite. The final compounds 8d, 8e, 8h, and 8k showed the highest hydrogen bond interactions with His-88 and Val-191 proteins and with water in all the proteins.

CuAAC-ensembled 1,2,3-triazole-linked isosteres as pharmacophores in drug discovery: review

The review lays emphasis on the significance of 1,2,3-triazoles synthesized via CuAAC reaction having potential to act as anti-microbial, anti-cancer, anti-viral, anti-inflammatory, anti-tuberculosis, anti-diabetic, and anti-Alzheimer drugs. The importance of click chemistry is due to its 'quicker' methodology that has the capability to create complex and efficient drugs with high yield and purity from simple and cheap starting materials. The activity of different triazolyl compounds was compiled considering MIC, IC50, and EC50 values against different species of microbes. In addition to this, the anti-oxidant property of triazolyl compounds have also been reviewed and discussed.

Biology-oriented drug synthesis (BIODS), in vitro urease inhibitory activity, and in silico studies on ibuprofen derivatives

Novel ibuprofen derivatives 1-19 including ibuprofen hydrazide 1, and substituted thiourea derivatives 2-19 were synthesized and characterized by EI-MS, FAB-MS, HREI-MS, HRFAB-MS, ¹H-, and ¹³C-NMR spectroscopic techniques. The synthetic molecules 1-19 were examined for their in vitro urease inhibition and were found to display a diversified degree of inhibitory potential in the range of IC₅₀ = 2.96-178 μM as compared to the standard thiourea (IC₅₀ = 21.32 ± 0.22 μM). Out of nineteen, thirteen derivatives 2-4, 6, 7, 9, 11-15, 17, and 18 demonstrated remarkable inhibitory activity with IC₅₀ values of 2.96 ± 1.11 to 16.1 ± 1.07 μM, compound 5 exhibited moderate inhibition with IC₅₀ value of 37.3 ± 0.41 μM, whereas, compounds 1, 8, and 10 demonstrated weak inhibition against urease enzyme. Almost all structural features are participating in the activity; however, limited structure-activity relationship was discussed on the basis of different structural features, i.e., different functional groups and their positions at aryl part. In addition, molecular docking study was performed in order to understand the ligands binding interactions with the active site of urease enzyme.

Semi-synthesis of β-keto-1,2,3-triazole derivatives from ethinylestradiol and evaluation of the cytotoxic activity

In this study, we report our contribution to the application of the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction for the synthesis of β-keto-1,2,3-triazole derivatives 3a-f from ethinylestradiol and their application in the inhibition of two human cancer cells lines: human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma (HepG2). The β-keto-1,2,3-triazole derivates 3a-f exhibited moderate cytotoxic activity for the HepG2 cells with IC₅₀ values of 29.7 μM (3a), 16.4 μM (3b), 17.8 μM (3c), 20.4 μM (3d), 28.1 μM (3e) and 28.2 μM (3f). The semi-synthetic β-keto-1,2,3-triazoles derivatives 3a-f were all characterized by FT-IR, NMR, HRMS and [α]_D.

New N-phenylacetamide-incorporated 1,2,3-triazoles: [Et3NH][OAc]-mediated efficient synthesis and biological evaluation

A facile, highly efficient, and greener method for the synthesis of new 1,4-disubstituted-1,2,3-triazoles was conducted using [Et3NH][OAc] as a medium by the implementation of ultrasound irradiation via click chemistry, affording excellent yields. The present synthetic method exhibited numerous advantages such as mild reaction conditions, excellent product yields, minimal chemical waste, operational simplicity, shorter reaction time, and a wide range of substrate scope. The synthesized compounds were further evaluated for in vitro antifungal activity against five fungal strains, and some of the compounds displayed equivalent or greater potency than the standard drug. A molecular docking study against the modelled three-dimensional structure of cytochrome P450 lanosterol 14α-demethylase was also performed to understand the binding affinity and binding interactions of the enzyme. Furthermore, the synthesized compounds were evaluated for DPPH radical scavenging activity and antitubercular activity against Mycobacterium tuberculosis H37Rv strain.

Synthesis and In Vitro and In Vivo Biological Activity Evaluation and Quantitative Proteome Profiling of Oxadiazoles Bearing Flexible Heterocyclic Patterns

A novel series of simple 1,3,4-oxadiazoles that bear flexible heterocyclic patterns was prepared, and their biological activities in plant pathogenic bacteria, fungi, oomycetes, and Meloidogyne incognita in vitro and in vivo were screened to explore low-cost and versatile antimicrobial agents. Screening results showed that compounds, such as A₀, B₀, and C₄, were bioactive against Xanthomonas oryzae pv oryzae in vitro and in vivo, and such bioactivities were superior to those of commercial agents bismerthiazol and thiodiazole copper. Their antibacterial mechanisms were further investigated by quantitative proteomics and concentration-dependent scanning electron microscopy images. Antifungal results indicated that compound A₀ displayed a selective and better antifungal effect on Botrytis cinerea with inhibition rate of 96.8% at 50 μg/mL. Nematocidal bioassays suggested that compound D₁ had good in vitro nematocidal activity toward M. incognita at 24, 48, and 72 h, with the corresponding insecticidal efficiency of 48.7%, 64.1%, and 87.2% at 40 μg/mL. In vivo study further confirmed that compounds D₁ and F₂ showed nematocidal actions at 80 μg/mL with a disease index of 1.5. Given these advantages, this kind of molecular frameworks could be a suitable platform for exploring highly efficient agrochemicals.

A Review Exploring Therapeutic Worth of 1,3,4-Oxadiazole Tailored Compounds

1,3,4-Oxadiazole, a five-membered aromatic ring can be seen in a number of synthetic molecules. The peculiar structural feature of 1,3,4-oxadiazole ring with pyridine type of nitrogen atom is beneficial for 1,3,4-oxadiazole derivatives to have effective binding with different enzymes and receptors in biological systems through numerous weak interactions, thereby eliciting an array of bioactivities. Research in the area of development of 1,3,4-oxadiazole-based derivatives has become an interesting topic for the scientists. A number of 1,3,4-oxadiazole based compounds with high therapeutic potency are being extensively used for the treatment of different ailments, contributing to enormous development value. This work provides a systematic and comprehensive review highlighting current developments of 1,3,4-oxadiazole based compounds in the entire range of medicinal chemistry such as anticancer, antifungal, antibacterial, antitubercular, anti-inflammatory, antineuropathic, antihypertensive, antihistaminic, antiparasitic, antiobesity, antiviral, and other medicinal agents. It is believed that this review will be of great help for new thoughts in the pursuit for rational designs for the development of more active and less toxic 1,3,4-oxadiazole based medicinal agents.

Immobilization of Planococcus sp. S5 Strain on the Loofah Sponge and Its Application in Naproxen Removal

Planococcus sp. S5, a Gram-positive bacterium isolated from the activated sludge is known to degrade naproxen in the presence of an additional carbon source. Due to the possible toxicity of naproxen and intermediates of its degradation, the whole cells of S5 strain were immobilized onto loofah sponge. The immobilized cells degraded 6, 9, 12 or 15 mg/L of naproxen faster than the free cells. Planococcus sp. cells immobilized onto the loofah sponge were able to degrade naproxen efficiently for 55 days without significant damage and disintegration of the carrier. Analysis of the activity of enzymes involved in naproxen degradation showed that stabilization of S5 cells in exopolysaccharide (EPS) resulted in a significant increase of their activity. Changes in the structure of biofilm formed on the loofah sponge cubes during degradation of naproxen were observed. Developed biocatalyst system showed high resistance to naproxen and its intermediates and degraded higher concentrations of the drug in comparison to the free cells.

Synthesis and antioxidant activity of 1,3,4-oxadiazoles and their diacylhydrazine precursors derived from phenolic acids

Eight 1,3,4-oxadiazoles and eight of their diacylhydrazine precursors were synthesized and examined for their antioxidative potential using different tests.