Synthesis, antimalarial and antioxidant activity of coumarin appended 1,4-disubstituted 1,2,3-triazoles

Synthesis and Investigation of Biological Activity of New Betulonic Acid Derivatives Containing 1,2,3-Triazole Fragments

The results of this study showed that the compounds synthesized by the authors have significant potential due to their antibacterial and cytotoxic properties. The apparent antibacterial activity demonstrated by the compounds suggests that they are active antimicrobial agents against common microbial pathogens that cause various socially significant infectious diseases. Compound 6 showed pronounced antimicrobial activity against the Gram-positive test strain Staphylococcus aureus ATCC 6538, and compound 7 demonstrated pronounced antimicrobial activity against the Gram-negative test strain Escherichia coli ATCC 25922 (MIC = 6.3 µg/mL). This allowed us to consider these compounds to have great potential.

Exploring the Recent Pioneering Developments of Small Molecules in Antimalarial Drug Armamentarium: A Chemistry Prospective Appraisal

Malaria is a very destructive and lethal parasitic disease that causes significant mortality worldwide, resulting in the loss of millions of lives annually. It is an infectious disease transmitted by mosquitoes, which is caused by different species of the parasite protozoan belonging to the genus Plasmodium. The uncontrolled intake of antimalarial drugs often employed in clinical settings has resulted in the emergence of numerous strains of plasmodium that are resistant to these drugs, including multidrug-resistant strains. This resistance significantly diminishes the effectiveness of many primary drugs used in the treatment of malaria. Hence, there is an urgent need for developing unique classes of antimalarial drugs that function with distinct mechanisms of action. In this context, the design and development of hybrid compounds that combine pharmacophoric properties from different lead molecules into a single unit gives a unique perspective towards further development of malaria drugs in the next generation. In recent years, the field of medicinal chemistry has made significant efforts resulting in the discovery and synthesis of numerous small novel compounds that exhibit potent antimalarial properties, while also demonstrating reduced toxicity and desirable efficacy. In light of this, we have reviewed the progress of hybrid antimalarial agents from 2021 up to the present. This manuscript presents a comprehensive overview of the latest advancements in the medicinal chemistry pertaining to small molecules, with a specific focus on their potential as antimalarial agents. As possible antimalarial drugs that might target both the dual stage and multi-stage stages of the parasite life cycle, these small hybrid molecules have been studied. This review explores a variety of physiologically active compounds that have been described in the literature in order to lay a strong foundation for the logical design and eventual identification of antimalarial drugs based on lead frameworks.

A Comprehensive Review of the Diverse Spectrum Activity of 1,2,3-Triazole-linked Isatin Hybrids

Heterocyclic compounds containing 1,2,3-triazole and isatin as core structures have emerged as promising drug candidates due to their diverse biological activities such as anti-cancer, antifungal, antimicrobial, antitumor, anti-epileptic, antiviral, and more. The presence of 1,2,3-triazoles and isatin heterocycles in these hybrids, both individually known for their medicinal significance, has increasingly piqued the interest of drug discovery researchers, as they seek to delve deeper into their extensive pharmacological potential for enhancing therapeutic efficacy. Moreover, these hybrid compounds are synthetically accessible using readily available materials. Therefore, there is a pressing need to provide a comprehensive overview of the existing knowledge in this field, offering valuable insights to readers and paving the way for the discovery of novel 1,2,3-triazole-linked isatin hybrids with therapeutic potential.

Umbelliferone and Its Synthetic Derivatives as Suitable Molecules for the Development of Agents with Biological Activities: A Review of Their Pharmacological and Therapeutic Potential

Umbelliferone (UMB), known as 7-hydroxycoumarin, hydrangine, or skimmetine, is a naturally occurring coumarin in the plant kingdom, mainly from the Umbelliferae family that possesses a wide variety of pharmacological properties. In addition, the use of nanoparticles containing umbelliferone may improve anti-inflammatory or anticancer therapy. Also, its derivatives are endowed with great potential for therapeutic applications due to their broad spectrum of biological activities such as anti-inflammatory, antioxidant, neuroprotective, antipsychotic, antiepileptic, antidiabetic, antimicrobial, antiviral, and antiproliferative effects. Moreover, 7-hydroxycoumarin ligands have been implemented to develop 7-hydroxycoumarin-based metal complexes with improved pharmacological activity. Besides therapeutic applications, umbelliferone analogues have been designed as fluorescent probes for the detection of biologically important species, such as enzymes, lysosomes, and endosomes, or for monitoring cell processes and protein functions as well various diseases caused by an excess of hydrogen peroxide. Furthermore, 7-hydroxy-based chemosensors may serve as a highly selective tool for Al3+ and Hg2+ detection in biological systems. This review is devoted to a summary of the research on umbelliferone and its synthetic derivatives in terms of biological and pharmaceutical properties, especially those reported in the literature during the period of 2017-2023. Future potential applications of umbelliferone and its synthetic derivatives are presented.

Triazole hybrid compounds: A new frontier in malaria treatment

Reviewing the advancements in malaria treatment, the emergence of triazole hybrid compounds stands out as a groundbreaking development. Combining the advantages of triazole and other moieties, these hybrid compounds offer a new frontier in the battle against malaria. Their potential as effective antimalarial agents has captured the attention of researchers and holds promise for overcoming the challenges posed by drug-resistant malaria strains. We focused on their broad spectrum of antimalarial activity of diverse hybridized 1,2,3-triazoles and 1,2,4-triazoles, structure-activity relationship (SAR), drug-likeness, bioavailability and pharmacokinetic properties reported since 2018 targeting multiple stages of the Plasmodium life cycle. This versatility makes them highly effective against both drug-sensitive and drug-resistant strains of P. falciparum, making them invaluable tools in regions where resistance is prevalent. The synergistic effects of combining the triazole moiety with other pharmacophores have resulted in even greater antimalarial potency. This approach has the potential to circumvent existing resistance mechanisms and provide a more sustainable solution to malaria treatment. While triazole hybrid compounds show great promise, further research and clinical trials are warranted to fully evaluate their safety, efficacy and long-term effects. As research progresses, these compounds can potentially revolutionize the field and contribute to global efforts to eradicate malaria, ultimately saving countless lives worldwide.

Current development of 1,2,3-triazole derived potential antimalarial scaffolds: Structure- activity relationship (SAR) and bioactive compounds

Malaria is among one of the most devastating and deadliest parasitic disease in the world claiming millions of lives every year around the globe. It is a mosquito-borne infectious disease caused by various species of the parasitic protozoan of the genus Plasmodium. The indiscriminate exploitation of the clinically used antimalarial drugs led to the development of various drug-resistant and multidrug-resistant strains of plasmodium which severely reduces the therapeutic effectiveness of most frontline medicines. Therefore, there is urgent need to develop novel structural classes of antimalarial agents acting with unique mechanism of action(s). In this context, design and development of hybrid molecules containing pharmacophoric features of different lead molecules in a single entity represents a unique strategy for the development of next-generation antimalarial drugs. Research efforts by the scientific community over the past few years has led to the identification and development of several heterocyclic small molecules as antimalarial agents with high potency, less toxicity and desired efficacy. Triazole derivatives have become indispensable units in the medicinal chemistry due to their diverse spectrum of biological profiles and many triazole based hybrids and conjugates have demonstrated potential in vitro and in vivo antimalarial activities. The manuscript compiled recent developments in the medicinal chemistry of triazole based small heterocyclic molecules as antimalarial agents and discusses various reported biologically active compounds to lay the groundwork for the rationale design and discovery of triazole based antimalarial compounds. The article emphasised on biological activities, structure activity relationships, and molecular docking studies of various triazole based hybrids with heterocycles such as quinoline, artemisinins, naphthyl, naphthoquinone, etc. as potential antimalarial agents which could act on the dual stage and multi stage of the parasitic life cycle.

Antimicrobial, antibiofilm, docking, DFT and molecular dynamics studies on click-derived isatin-thiosemicarbazone-1,2,3-triazoles

In an effort to develop new antimicrobial and antibiofilm agents, we have designed and synthesized a novel class of isatin-thiosemicarbazone-1,2,3-triazoles through the CuAAC approach. All the synthesized hybrids were characterized by several spectral techniques such as FTIR, 1H NMR, 13C NMR, 2D NMR and HRMS. All the derivatives were evaluated for their antimicrobial and antibiofilm efficacy towards various microbial species. Triazole hybrid 8d exhibited the highest efficacy towards E. coli (MIC = 0.0067 µmol/mL) and S. aureus (MIC = 0.0067 µmol/mL), whereas, compounds 8b, 8c, 8d, 8e, 9a and terminal alkyne (10) significantly inhibited biofilm formation against S. aureus, B. subtilis and E. coli. To find out the structure-activity relationship and binding interactions of synthesized hybrids with enzymes 1KZN and 5TZ1, molecular docking for all the synthesized hybrids was carried out. DFT calculations for all hybrids and the molecular dynamics studies for compounds 9e and 9f were also performed to support the biological behavior of these hybrids.Communicated by Ramaswamy H. Sarma.

Novel Oleanolic Acid-Phtalimidines Tethered 1,2,3 Triazole Hybrids as Promising Antibacterial Agents: Design, Synthesis, In Vitro Experiments and In Silico Docking Studies

As part of the valorization of agricultural waste into bioactive compounds, a series of structurally novel oleanolic acid ((3β-hydroxyolean-12-en-28-oic acid, OA-1)-phtalimidines (isoindolinones) conjugates 18a-u bearing 1,2,3-triazole moieties were designed and synthesized by treating an azide 4 previously prepared from OA-1 isolated from olive pomace (Olea europaea L.) with a wide range of propargylated phtalimidines using the Cu(I)-catalyzed click chemistry approach. OA-1 and its newly prepared analogues, 18a-u, were screened in vitro for their antibacterial activity against two Gram-positive bacteria, Staphylococcus aureus and Listeria monocytogenes, and two Gram-negative bacteria, Salmonella thyphimurium and Pseudomonas aeruginosa. Attractive results were obtained, notably against L. monocytogenes. Compounds 18d, 18g, and 18h exhibited the highest antibacterial activity when compared with OA-1 and other compounds in the series against tested pathogenic bacterial strains. A molecular docking study was performed to explore the binding mode of the most active derivatives into the active site of the ABC substrate-binding protein Lmo0181 from L. monocytogenes. Results showed the importance of both hydrogen bonding and hydrophobic interactions with the target protein and are in favor of the experimental data.

Antioxidant Activity of Coumarins and Their Metal Complexes

Ubiquitously present in plant life, coumarins, as a class of phenolic compounds, have multiple applications-in everyday life, in organic synthesis, in medicine and many others. Coumarins are well known for their broad spectrum of physiological effects. The specific structure of the coumarin scaffold involves a conjugated system with excellent charge and electron transport properties. The antioxidant activity of natural coumarins has been a subject of intense study for at least two decades. Significant research into the antioxidant behavior of natural/semi-synthetic coumarins and their complexes has been carried out and published in scientific literature. The authors of this review have noted that, during the past five years, research efforts seem to have been focused on the synthesis and examination of synthetic coumarin derivatives with the aim to produce potential drugs with enhanced, modified or entirely novel effects. As many pathologies are associated with oxidative stress, coumarin-based compounds could be excellent candidates for novel medicinal molecules. The present review aims to inform the reader on some prominent results from investigations into the antioxidant properties of novel coumarin compounds over the past five years.

Antimicrobial, Antiproliferative Effects and Docking Studies of Methoxy Group Enriched Coumarin-Chalcone Hybrids

Methoxy group enriched eight coumarin-chalcone hybrid derivatives were synthesized. Antimicrobial/ antiproliferative activities were tested against eight human pathogenic microorganisms and four cancer cell lines (AGS, HepG2, MCF-7 and PC-3), respectively. Antimicrobial results showed that most of the compounds were almost more active than used standard antibiotics. Cytotoxicity results showed that 2,3,4-trimethoxyphenyl and thiophene containing structures have promising antiproliferative effects against AGS gastric cell lines with ∼5 μg/ml IC₅₀ values. At the same time, 2,4-dimethoxyphenyl bearing derivative exhibited the lowest IC₅₀ values against HepG2 (∼10 μg/ml) and PC-3 (∼5 μg/ml) cell lines. Particularly, the cell viabilities of MCF-7 cell lines were remarkably inhibited by all the compounds with lower IC₅₀ values. Therefore, molecular docking studies between hybrid ligands and quinone reductase-2 enzyme (regulates in MCF-7 cancer cells) were performed. The results demonstrated that all the derivatives can smoothly interact with interested enzyme in agreement with the experimental results. Finally, ADME parameters were studied to reveal drug-likeness potentials of the coumarin-chalcone hybrids.

Fractions 14 and 36K of Metabolite Extract Streptomyces hygroscopicus subsp. Hygroscopicus Have Antimalarial Activities Against Plasmodium berghei in vitro

Purpose

The study was conducted to investigate the effectivity and the cytotoxicity of fractions 14 and 36K of metabolite extract of Streptomyces hygroscopicus subsp. Hygroscopicus as an antimalarial compounds against Plasmodium berghei in vitro.

Methods

Fractions 14 and 36K of metabolite extract of Streptomyces hygroscopicus subsp. Hygroscopicus produced by the fractionation process utilizing the Flash Column Chromatography (FCC) BUCHI Reveleris^® PREP. Plasmodium berghei culture was used to assess the antimalarial activity of fractions 14 and 36K. Parasite densities and the ability of parasite growth were determined under microscopic. The cytotoxicity of the fractions was assessed using MTT assays on the MCF-7 cell line.

Results

Streptomyces hygroscopicus subsp. Hygroscopicus fractions 14 and 36K have antimalarial activity against Plasmodium berghei, with fraction 14 having the more potent activity. The percentage of Plasmodium berghei-infected erythrocytes was decreased as well as the increase of fraction concentration. Fraction 14 has the highest inhibition of parasite growth at a concentration of 156,25 μg/mL, with an inhibition percentage of 67.73% (R² = 0.953, p = 0.000). IC₅₀ of fractions 14 and 36K were found at 10.63 μg/mL and 135,91 μg/mL, respectively. The fractions caused morphological damage in almost all asexual stages of the parasite. Both fractions were not toxic against MCF-7, indicating that the fractions have a safe active metabolite.

Conclusion

Fractions 14 and 36K of metabolite extract Streptomyces hygroscopicus subsp. Hygroscopicus contains non-toxic compounds that could damage the morphology and inhibit the growth of Plasmodium berghei in vitro.

Synthesis, antimicrobial evaluation and docking studies of fluorinated imine linked 1,2,3-triazoles

A diverse series of imine linked 1,2,3-triazole hybrids has been synthesized via Cu(I)-promoted click reaction, with an aim to develop some new antimicrobial molecules. The structural characterization of the synthesized triazole hybrids was accomplished using various spectral techniques like ¹H NMR, ¹³C NMR, FTIR and HRMS. Among the synthesized hybrids, 7d exhibited highest antimicrobial efficacy against R. oryzae and S. aureus with MIC of 0.0123 µmol/mL and 0.0061 µmol/mL, respectively. Docking studies of the terminal alkynes (4a, 4b) and triazole hybrids (6a, 6d, 7c, 7g) showing high potency towards E. coli DNA gyrase and C. albicans sterol 14-α demethylase were also undertaken to understand the binding behaviour.