Home Microwave and Cs+-assisted chemo selective reaction protocol for synthesizing 2-styryl quinoline biorelevant molecules
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Microwave and Cs+-assisted chemo selective reaction protocol for synthesizing 2-styryl quinoline biorelevant molecules

  • Ravi Kumar Mittal , Priyank Purohit EMAIL logo , Magda H. Abdellattif and Meenu Aggarwal
Published/Copyright: March 24, 2023

Abstract

The reaction protocols and their continuous development to achieve the desired selectivity remain a primary target of organic chemistry, which is addressed here with the specific role of the cesium ion. The pharmacophore “2-styryl quinoline” was taken as a reference here because of the continuation of our work, where it was found fit as fusion inhibitors and anti-viral agents. The present protocol defines its importance for the synthesis of O-alkylated products. However, in most cases, N-alkylation proceeds because of nitrogen atoms’ more nucleophilic nature and electronic density. The cesium effect makes this possible because of the large cationic size and its affection for the oxygen atom. The plausible mechanism and its progression were demonstrated here with the help of density function theory calculation by analyzing the energy of intermediates. The protocol is also found suitable with microwave irradiation. Moreover, it gives the product a better yield in less reaction time. The present reaction protocol and its importance will address some of the crucial issues related to the synthesis of the complex molecule, and the present protocol will open up hope, where the selectivity and product yield would be a concern.

1 Introduction

Synthesis of the heterocyclic scaffold with ease has always been a challenge. However, many lucrative methods have evolved [1,2], but the synthesis or functionalization of the complex substrate is the most challenging task, a significant problem encountered with the region and chemo non-selectivity. The reaction with selectivity has always been a Herculean task concerning their region and stereo outcomes. Here we are developing a protocol for the selective O-alkylation over the N-alkylation, which is more prone to react because of its size and nucleophilicity [3]. The present protocol was developed using 2-styryl quinoline moiety, which was used as DNA binding [4], anti-cancer agents [5,6,7,8,9,10], and viral fusion inhibitors [11,12]. This activity makes the nucleus more valuable, and the reaction protocol gives direct value addition to the molecule through its selective substitution (Figure 1).

Figure 1 
               2-Styryl quinoline pharmacophore and its pharmacological spectrum [8–21].
Figure 1

2-Styryl quinoline pharmacophore and its pharmacological spectrum [821].

The 2-styryl quinolines are pharmacologically active molecules [13], reported with various other activities like anti-HIV-1 [14], antimicrobial[15], antimalarial [16], and anti-Alzheimer properties [17]. Some of the significant work on the 2-styryl quinoline was given attention for the drug discovery purpose. Among them, Chang et al. developed a series of styryl quinolines that were found to be effective anticancer agents [18]. Mrozek-Wilczkiewicz et al. demonstrated that styryl quinoline derivatives have significant anti-proliferative activity against human colon carcinoma cell lines [19]. El-Sayed et al. discovered a new class of 4,6-disubstituted 2-(4-(dimethylamino)styryl)quinolines with anticancer activity [8]. Mekouar et al. identified certain styryl quinoline compounds as a new class of powerful HIV-1 IN blockers that inhibited HIV replication ex vivo that were devoid of cytotoxicity at concentrations up to 100 mM [20]. Zouhiri et al. reported a number of new styryl quinoline analogues in order to investigate the SAR of inhibitors and show that the occurrence of a carboxyl group and a hydroxyl group at the C-7 and C-8 positions of the quinoline was needed for the drug’s biological activity [21].

The search for the best fit molecule led us to the synthesis of 4-alkoxy quinoline derivatives (2) from the Quinolone (1) molecules through the alkylation reaction. However, some of the previously reported reactions were not favorable because of their selectivity over Nitrogen (N) and Oxygen (O) atom [22,23]. The nitrogen atom possesses more electronic density and is more prone to nucleophilic reaction toward electrophilic species (Figure 2).

Figure 2 
               
                  O-Alkylation of the 2-styryl quinolone [8,9,10,11,12].
Figure 2

O-Alkylation of the 2-styryl quinolone [8,9,10,11,12].

Several reactions and conditions have been attempted with the conventional base like K2CO3 and NaOH to carry out the O-alkylation, but the result was not found to be satisfactory, as it is shown in the entries 2 and 3 of Table 1, the entire starting material was recovered; moreover, in entry 1, low yield (only 20%) was observed and the remaining starting materials were also recovered (Table 1, entries 1–3). However, the further use of cesium with the 1.5 and 3.5 equivalent amounts was satisfactory in the DMF solvent. The, microwave irradiation was found synergistic for improving the product yields. It was also observed that the Cesium ion (Cs+) is also important for reaction in the microwave irradiation condition (Table 1, entry 7); however, the comparison with other carbonates also confirms the role of Cs+ (Table 2). The high yield and selective reaction protocol with lesser time make this reaction greener with multiple advantages.

Table 1

Reaction conditions for O-alkylation of (E)-2-styryl quinoline-4-ol

S. No. Reagents Conditions Yields (%)
1. K2CO3, DMF 80°C, 12 h 20
2. NaH, THF RT, 12 h No product
3. NaOH RT, 12 h No product
NaH, DMF
4. Cs2CO3 (1.5 equiv.), DMF RT, 24 h 20
5. Cs2CO3 (3.5 equiv.), DMF 80°C, 3.5 h 57–74a
6. Cs2CO3 (1.5 equiv.), DMF MW, 15 min 60–78
7. DMF MW, 15 min 0 b

avaried depending upon alkyl chain, bstarting material was recovered.

Table 2

Optimization of the reaction condition using other carbonate base

S. No. Reagents Conditions Yieldsa (%)
1. Cs2CO3 (1.5 equiv.), DMF MW, 15 min 74
2. Li2CO3 (1.5 equiv.), DMF MW, 15 min 0b
3. K2CO3 (1.5 equiv.), DMF MW, 15 min 0b
4. Na2CO3 (1.5 equiv.), DMF MW, 15 min 0b

aYield calculated after chromatographic isolation; bstarting material were recovered.

The effect of Cs+ signifies the importance of the O-alkylation with the high level of selectivity. Compared to other cations, the large cationic radius of the ions makes the Cs+ naked and reactive in the non-polar solvents.

The solvent optimization study was also done with various non-polar solvents like dimethyl sulfoxide (DMSO), N-Methyl-2-pyrrolidone (NMP), and dimethylacetamide (DMP), but the role of the polar aprotic was found similar in all the aprotic solvents. The choice of the solvent was done based on the rate and boiling point of the solvents and the DMF was kept constant for further optimization of the substrate scope. The role of Cs+ shows selectivity because of its not too strong and too weak character. Various reported experiments also define the unique role of Cs+ in the aprotic solvents, with their cationic character, to develop a selective protocol [24,25]. To find the reaction mechanism, the energy minimization process was done with the density function theory (DFT) calculation protocol described in Section 2.

2 Experimental method (DFT)

Gaussian 16 package was used to perform all the calculations utilizing DFT-based methodologies. The ground state was optimized using various methods such as B3LYP, LSDA, and B3PW91, along with the 6-311 + G(d,p) basis set. HOMO and LUMO energy values were used to calculate the variety of global reactivity descriptors and defined as follows [26]:

χ ( electronegativity ) = 1 2 ( E HOMO + E LUMO ) ,

µ ( chemical potential ) = χ ,

η ( chemical hardness ) = 1 2 ( E LOMO E HOMO ) ,

S ( chemical softness ) = 1 2 η ,

ω ( electrophilicity index ) = μ 2 2 η .

2.1 DFT

In order to find out the geometry and to calculate the variety of parameters such as chemical reactivity, kinetic stability, and optoelectronic attributes of a molecule, DFT-based methods have been used. First, to assess the computational cost and reliability, prescreening was carried out by utilizing various DFT-based methods. From the observation, it was observed that B3LYP/6-311 + G(d,p) is the perfect method based on correlation derived from zero point energy. After that, to explore the titled compound’s electrostatic parameters, the energy of HOMO and LUMO in the gas phase was calculated utilizing the B3LYP/6-311 + G(d,p) level of theory as frontier molecular orbitals play a significant role in determining the wide range of intermolecular interactions present within the molecule. The molecular stability and chemical and spectro-chemical properties of a molecule can be assessed by the energy gap between HOMO and LUMO. As can be seen from Figure 3, HOMO and LUMO are found to be localized on the 2-styryl quinoline ring. The energy difference between HOMO and LUMO was found to be 3.908 eV which revealed the high stability of the molecule. The concept of chemical potential, which defines a molecule’s electron donating and withdrawing capacity. The greater the potential chemical values, the higher the molecules’ tendency to donate electrons. Chemical hardness describes the capability of the molecule to withstand the alteration in electron density. The more significant energy difference between HOMO and LUMO leads to harder molecules and high stability. The electrophilicity index (ω) tells us about the energy of stabilization of the molecule after accepting an electron; the lower the value of the electrophilicity index, the better the nucleophilicity of the molecule. The range of global reactivity parameters such as chemical potential and softness, chemical hardness, and electronegativity was calculated using the HOMO-LUMO energy difference outlined in Table 3.

Figure 3 
                  Molecular orbital diagram for 2a.
Figure 3

Molecular orbital diagram for 2a.

Table 3

Calculated energy and global descriptors

Compounds HOMO (eV) LUMO (eV) Chemical hardness (µ) Global hardness, η = −µ Global electrophilicity index, ω = µ 2/2η Softness, s = 1/η
2a −5.990 −2.082 −4.036 4.036 2.018 0.248
2b −5.993 −2.085 −4.039 4.039 2.020 0.248
2c −5.979 −2.070 −4.025 4.025 2.012 0.248
2d −5.907 −1.986 −3.947 3.947 1.973 0.253
2e −5.909 −1.988 −3.949 3.949 1.974 0.253
2f −5.985 −2.080 −4.033 4.033 2.016 0.248
2g −5.502 −2.062 −3.782 3.782 1.891 0.264
2h −5.961 −2.044 −4.003 4.003 2.001 0.250
2i −5.883 −1.965 −3.924 3.924 1.962 0.255

2.2 MM2 energy calculation through Gaussian 16

The mechanism of the reaction was carried out, and the energy calculation of the compounds and its intermediate study suggest the thermodynamic pattern and the energy study claims that the O-alkylation and the Cs+-based intermediate also confirm that the positive process through the attachment of Cs+ to oxygen makes this reaction possible. The energy of the O-alkylated product and its Cs+ abduct its thermodynamic behaviors and process probability to get the O-alkylated products over the N-alkylation (which has high energy) (Figure 4).

Figure 4 
                  Energy of intermediate and the product.
Figure 4

Energy of intermediate and the product.

The plausible mechanism or role of the Cs+ was depicted through the below mechanistic representation, with the HOMO–LUMO energy calculation of the compounds 2d and 3a where the R corresponds to the ethyl groups. The energy of the compounds 2d and 3a is 13.96 and 39.17 kcal/mol, respectively, which clearly shows that compound 2d has the possibility of formation through thermodynamics, which is more stable. Moreover, the HOMO-LUMO energy gap of compound 2d is 3.9 eV and 3a is 4.2 eV, which also confirms the possibility of the formation of the compound 2d instead of 3a (Figure 5).

Figure 5 
                  Plausible mechanism of the O-alkylation.
Figure 5

Plausible mechanism of the O-alkylation.

The mechanism of the formation of compound 2d claims that the initiation of reaction starts with the attraction of the oxygen atom and Cs+ because of its well-established affection toward the oxygen atom. The attraction and the ionic bond are compensated with the response from the non-bonding electron of the nitrogen, which makes the reaction feasible from the oxygen side. The reaction ends with the stabilization of the charge with a unique O-alkylated product, which is also justified by the DFT calculation [23,27].

The optimized reaction condition was found to use Cs2CO3 (3.5 equiv.) in DMF for 15–20 min in microwave irradiation conditions for the synthesis of O-4-alkyl derivatives of 2-styryl quinoline based on the strategy shown in Scheme 1. As a result, a series of eight new O-4-alkylated derivatives were synthesized by the modification of the hydroxyl group present at the four positions of the 2-styryl quinoline ring with a wide range of substituents such as ethyl, propyl, butyl, isopropyl, isobutyl, neopentyl, allyl, etc. In addition, the pharmacophore confirmed the broad spectrum anti-viral activity because of their reported affinity towards the spike protein.

Scheme 1 
                  Synthesis of 4-substituted 2-styryl quinoline derivatives (2a–i).
Scheme 1

Synthesis of 4-substituted 2-styryl quinoline derivatives (2a–i).

3 Discussion

All the newly synthesized compounds were characterized using HRMS, 1H NMR, 13C NMR, IR, and melting point. The formula for compound 2h was established as C20H17NO. Based on ESI-HRMS data m/z found 310.1204 [M + Na]+ (calcd m/z 310.1202 for [M + Na]+). In the IR spectrum, the signal at 1,100 cm−1 revealed the presence of olefin.

Combined analysis of the 1H NMR (Figure 6) and 13C NMR (Figure 7) spectroscopy data revealed the presence of 10 protons in the aromatic region, 20 carbons in the range of δ value of 161–68 ppm, and 1 carbon at the δ value of 68.96, 98.27, 117.12, 120.58, 121.51, 125.27, 126.92, 126.97, 127.89, 128.50, 128.53, 130.06, 132.28, 135.02, 136.33, 148.31, 157.56, 161.69 ppm. The 1H–1H COSY correlations H-13 with H-14, H-14 with H-13, H-15a, and H-15b, and H-15a with H-14 and H-15b showed the connectivity of adjacent protons (Figure 8). In the HMBC spectrum, H-3 was correlated with carbon at δ 161.69 (C-4) and 157.56 (C-2). H-13 was correlated with carbon at δ 161.69 (C-4), 132.28 (C-14), and 117.12 (C-15), while H-14 was correlated with carbon at δ 68.96 (C-13). H-15 was correlated with carbon at δ 68.96 (C) and 132.2 (C-14) (Figure 9).

Figure 6 
               
                  1H NMR spectrum of compound 2h in methanol-d
                  4.
Figure 6

1H NMR spectrum of compound 2h in methanol-d 4.

Figure 7 
               
                  13C NMR spectrum of compound 2h in methanol-d
                  4.
Figure 7

13C NMR spectrum of compound 2h in methanol-d 4.

Figure 8 
               
                  1H–1H COSY spectrum of compound 2h in methanol-d
                  4.
Figure 8

1H–1H COSY spectrum of compound 2h in methanol-d 4.

Figure 9 
               
                  1H–1H HMBC spectrum of compound 2h in methanol-d
                  4.
Figure 9

1H–1H HMBC spectrum of compound 2h in methanol-d 4.

The HMBC experiment confirmed alkylation at the 4-OH position; in the case of compound 2h, methylene proton (δ 4.84) of allyl moiety attached at 4-OH of (E)-2-styryl quinoline-4-ol showed a correlation with carbon at 4-position (δ 161.69) as depicted in Figure 10.

Figure 10 
               Structure elucidation of compound 2h.
Figure 10

Structure elucidation of compound 2h.

4 Conclusion

Quinoline scaffold is widely present in several natural and synthetic molecules. The molecules containing this scaffold have different pharmacological activities explored to obtain potent anti-viral and anti-cancer activity. A series of 25 new O-4-alkylated styryl quinoline derivatives were synthesized by modification of the hydroxyl group present at the 4 positions of the 2-styryl quinoline ring with a wide range of alkyl substituents using cesium carbonate as base and DMF as solvent at 80°C for 3.5 h, which were found to be the optimum reaction condition for O-4 alkylation of 2-styryl quinoline. Furthermore, the reaction was claimed to be greener because of its suitability in microwave irradiation conditions. The synthesis of these compounds with high selectivity can be helpful in the future HTS screening of compounds for a suitable target.



  1. Funding information: This research was financially supported by Taif University (project TURS2020/91).

  2. Author contributions: Ravi Kumar Mittal: synthesis, characterization, and software; Priyank Purohit: methodology, investigation, and writing the draft; Magda H. Abdellattif: funding acquisition, software, and final editing; Meenu Aggarwal: instrumentation, project administration, and software.

  3. Conflict of interest: The authors declare that there is no conflict of interest.

  4. Ethical approval: The conducted research is not related to either human or animal use.

  5. Data availability statement: All data generated or analyzed during this study are included in this published article.

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Received: 2022-09-28
Revised: 2022-10-23
Accepted: 2022-11-03
Published Online: 2023-03-24

© 2023 the author(s), published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 International License.

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  50. Chloramine-T-induced oxidation of Rizatriptan Benzoate: An integral chemical and spectroscopic study of products, mechanisms and kinetics
  51. Study on antioxidant and antimicrobial potential of chemically profiled essential oils extracted from Juniperus phoenicea (L.) by use of in vitro and in silico approaches
  52. Screening and characterization of fungal taxol-producing endophytic fungi for evaluation of antimicrobial and anticancer activities
  53. Mineral composition, principal polyphenolic components, and evaluation of the anti-inflammatory, analgesic, and antioxidant properties of Cytisus villosus Pourr leaf extracts
  54. In vitro antiproliferative efficacy of Annona muricata seed and fruit extracts on several cancer cell lines
  55. An experimental study for chemical characterization of artificial anterior cruciate ligament with coated chitosan as biomaterial
  56. Prevalence of residual risks of the transfusion-transmitted infections in Riyadh hospitals: A two-year retrospective study
  57. Computational and experimental investigation of antibacterial and antifungal properties of Nicotiana tabacum extracts
  58. Reinforcement of cementitious mortars with hemp fibers and shives
  59. X-ray shielding properties of bismuth-borate glass doped with rare earth ions
  60. Green supported silver nanoparticles over modified reduced graphene oxide: Investigation of its antioxidant and anti-ovarian cancer effects
  61. Orthogonal synthesis of a versatile building block for dual functionalization of targeting vectors
  62. Thymbra spicata leaf extract driven biogenic synthesis of Au/Fe3O4 nanocomposite and its bio-application in the treatment of different types of leukemia
  63. The role of Ag2O incorporation in nuclear radiation shielding behaviors of the Li2O–Pb3O4–SiO2 glass system: A multi-step characterization study
  64. A stimuli-responsive in situ spray hydrogel co-loaded with naringenin and gentamicin for chronic wounds
  65. Assessment of the impact of γ-irradiation on the piperine content and microbial quality of black pepper
  66. Antioxidant, sensory, and functional properties of low-alcoholic IPA beer with Pinus sylvestris L. shoots addition fermented using unconventional yeast
  67. Screening and optimization of extracellular pectinase produced by Bacillus thuringiensis SH7
  68. Determination of polyphenols in Chinese jujube using ultra-performance liquid chromatography–mass spectrometry
  69. Synergistic effects of harpin and NaCl in determining soybean sprout quality under non-sterile conditions
  70. Field evaluation of different eco-friendly alternative control methods against Panonychus citri [Acari: Tetranychidae] spider mite and its predators in citrus orchards
  71. Exploring the antimicrobial potential of biologically synthesized zero valent iron nanoparticles
  72. NaCl regulates goldfish growth and survival at three food supply levels under hypoxia
  73. An exploration of the physical, optical, mechanical, and radiation shielding properties of PbO–MgO–ZnO–B2O3 glasses
  74. A novel statistical modeling of air pollution and the COVID-19 pandemic mortality data by Poisson, geometric, and negative binomial regression models with fixed and random effects
  75. Treatment activity of the injectable hydrogels loaded with dexamethasone In(iii) complex on glioma by inhibiting the VEGF signaling pathway
  76. An alternative approach for the excess lifetime cancer risk and prediction of radiological parameters
  77. Panax ginseng leaf aqueous extract mediated green synthesis of AgNPs under ultrasound condition and investigation of its anti-lung adenocarcinoma effects
  78. Study of hydrolysis and production of instant ginger (Zingiber officinale) tea
  79. Novel green synthesis of zinc oxide nanoparticles using Salvia rosmarinus extract for treatment of human lung cancer
  80. Evaluation of second trimester plasma lipoxin A4, VEGFR-1, IL-6, and TNF-α levels in pregnant women with gestational diabetes mellitus
  81. Antidiabetic, antioxidant and cytotoxicity activities of ortho- and para-substituted Schiff bases derived from metformin hydrochloride: Validation by molecular docking and in silico ADME studies
  82. Antioxidant, antidiabetic, antiglaucoma, and anticholinergic effects of Tayfi grape (Vitis vinifera): A phytochemical screening by LC-MS/MS analysis
  83. Identification of genetic polymorphisms in the stearoyl CoA desaturase gene and its association with milk quality traits in Najdi sheep
  84. Cold-acclimation effect on cadmium absorption and biosynthesis of polyphenolics, and free proline and photosynthetic pigments in Spirogyra aequinoctialis
  85. Analysis of secondary metabolites in Xinjiang Morus nigra leaves using different extraction methods with UPLC-Q/TOF-MS/MS technology
  86. Nanoarchitectonics and performance evaluation of a Fe3O4-stabilized Pickering emulsion-type differential pressure plugging agent
  87. Investigating pyrolysis characteristics of Shengdong coal through Py-GC/MS
  88. Extraction, phytochemical characterization, and antifungal activity of Salvia rosmarinus extract
  89. Introducing a novel and natural antibiotic for the treatment of oral pathogens: Abelmoschus esculentus green-formulated silver nanoparticles
  90. Optimization of gallic acid-enriched ultrasonic-assisted extraction from mango peels
  91. Effect of gamma rays irradiation in the structure, optical, and electrical properties of samarium doped bismuth titanate ceramics
  92. Combinatory in silico investigation for potential inhibitors from Curcuma sahuynhensis Škorničk. & N.S. Lý volatile phytoconstituents against influenza A hemagglutinin, SARS-CoV-2 main protease, and Omicron-variant spike protein
  93. Physical, mechanical, and gamma ray shielding properties of the Bi2O3–BaO–B2O3–ZnO–As2O3–MgO–Na2O glass system
  94. Twofold interpenetrated 3D Cd(ii) complex: Crystal structure and luminescent property
  95. Study on the microstructure and soil quality variation of composite soil with soft rock and sand
  96. Ancient spring waters still emerging and accessible in the Roman Forum area: Chemical–physical and microbiological characterization
  97. Extraction and characterization of type I collagen from scales of Mexican Biajaiba fish
  98. Finding small molecular compounds to decrease trimethylamine oxide levels in atherosclerosis by virtual screening
  99. Prefatory in silico studies and in vitro insecticidal effect of Nigella sativa (L.) essential oil and its active compound (carvacrol) against the Callosobruchus maculatus adults (Fab), a major pest of chickpea
  100. Polymerized methyl imidazole silver bromide (CH3C6H5AgBr)6: Synthesis, crystal structures, and catalytic activity
  101. Using calcined waste fish bones as a green solid catalyst for biodiesel production from date seed oil
  102. Influence of the addition of WO3 on TeO2–Na2O glass systems in view of the feature of mechanical, optical, and photon attenuation
  103. Naringin ameliorates 5-fluorouracil elicited neurotoxicity by curtailing oxidative stress and iNOS/NF-ĸB/caspase-3 pathway
  104. GC-MS profile of extracts of an endophytic fungus Alternaria and evaluation of its anticancer and antibacterial potentialities
  105. Green synthesis, chemical characterization, and antioxidant and anti-colorectal cancer effects of vanadium nanoparticles
  106. Determination of caffeine content in coffee drinks prepared in some coffee shops in the local market in Jeddah City, Saudi Arabia
  107. A new 3D supramolecular Cu(ii) framework: Crystal structure and photocatalytic characteristics
  108. Bordeaux mixture accelerates ripening, delays senescence, and promotes metabolite accumulation in jujube fruit
  109. Important application value of injectable hydrogels loaded with omeprazole Schiff base complex in the treatment of pancreatitis
  110. Color tunable benzothiadiazole-based small molecules for lightening applications
  111. Investigation of structural, dielectric, impedance, and mechanical properties of hydroxyapatite-modified barium titanate composites for biomedical applications
  112. Metal gel particles loaded with epidermal cell growth factor promote skin wound repair mechanism by regulating miRNA
  113. In vitro exploration of Hypsizygus ulmarius (Bull.) mushroom fruiting bodies: Potential antidiabetic and anti-inflammatory agent
  114. Alteration in the molecular structure of the adenine base exposed to gamma irradiation: An ESR study
  115. Comprehensive study of optical, thermal, and gamma-ray shielding properties of Bi2O3–ZnO–PbO–B2O3 glasses
  116. Lewis acids as co-catalysts in Pd-based catalyzed systems of the octene-1 hydroethoxycarbonylation reaction
  117. Synthesis, Hirshfeld surface analysis, thermal, and selective α-glucosidase inhibitory studies of Schiff base transition metal complexes
  118. Protective properties of AgNPs green-synthesized by Abelmoschus esculentus on retinal damage on the virtue of its anti-inflammatory and antioxidant effects in diabetic rat
  119. Effects of green decorated AgNPs on lignin-modified magnetic nanoparticles mediated by Cydonia on cecal ligation and puncture-induced sepsis
  120. Treatment of gastric cancer by green mediated silver nanoparticles using Pistacia atlantica bark aqueous extract
  121. Preparation of newly developed porcelain ceramics containing WO3 nanoparticles for radiation shielding applications
  122. Utilization of computational methods for the identification of new natural inhibitors of human neutrophil elastase in inflammation therapy
  123. Some anticancer agents as effective glutathione S-transferase (GST) inhibitors
  124. Clay-based bricks’ rich illite mineral for gamma-ray shielding applications: An experimental evaluation of the effect of pressure rates on gamma-ray attenuation parameters
  125. Stability kinetics of orevactaene pigments produced by Epicoccum nigrum in solid-state fermentation
  126. Treatment of denture stomatitis using iron nanoparticles green-synthesized by Silybum marianum extract
  127. Characterization and antioxidant potential of white mustard (Brassica hirta) leaf extract and stabilization of sunflower oil
  128. Characteristics of Langmuir monomolecular monolayers formed by the novel oil blends
  129. Strategies for optimizing the single GdSrFeO4 phase synthesis
  130. Oleic acid and linoleic acid nanosomes boost immunity and provoke cell death via the upregulation of beta-defensin-4 at genetic and epigenetic levels
  131. Unraveling the therapeutic potential of Bombax ceiba roots: A comprehensive study of chemical composition, heavy metal content, antibacterial activity, and in silico analysis
  132. Green synthesis of AgNPs using plant extract and investigation of its anti-human colorectal cancer application
  133. The adsorption of naproxen on adsorbents obtained from pepper stalk extract by green synthesis
  134. Treatment of gastric cancer by silver nanoparticles encapsulated by chitosan polymers mediated by Pistacia atlantica extract under ultrasound condition
  135. In vitro protective and anti-inflammatory effects of Capparis spinosa and its flavonoids profile
  136. Wear and corrosion behavior of TiC and WC coatings deposited on high-speed steels by electro-spark deposition
  137. Therapeutic effects of green-formulated gold nanoparticles by Origanum majorana on spinal cord injury in rats
  138. Melanin antibacterial activity of two new strains, SN1 and SN2, of Exophiala phaeomuriformis against five human pathogens
  139. Evaluation of the analgesic and anesthetic properties of silver nanoparticles supported over biodegradable acacia gum-modified magnetic nanoparticles
  140. Review Articles
  141. Role and mechanism of fruit waste polyphenols in diabetes management
  142. A comprehensive review of non-alkaloidal metabolites from the subfamily Amaryllidoideae (Amaryllidaceae)
  143. Discovery of the chemical constituents, structural characteristics, and pharmacological functions of Chinese caterpillar fungus
  144. Eco-friendly green approach of nickel oxide nanoparticles for biomedical applications
  145. Advances in the pharmaceutical research of curcumin for oral administration
  146. Rapid Communication
  147. Determination of the contents of bioactive compounds in St. John’s wort (Hypericum perforatum): Comparison of commercial and wild samples
  148. Retraction
  149. Retraction of “Two mixed-ligand coordination polymers based on 2,5-thiophenedicarboxylic acid and flexible N-donor ligands: The protective effect on periodontitis via reducing the release of IL-1β and TNF-α”
  150. Topical Issue on Phytochemicals, biological and toxicological analysis of aromatic medicinal plants
  151. Anti-plasmodial potential of selected medicinal plants and a compound Atropine isolated from Eucalyptus obliqua
  152. Anthocyanin extract from black rice attenuates chronic inflammation in DSS-induced colitis mouse model by modulating the gut microbiota
  153. Evaluation of antibiofilm and cytotoxicity effect of Rumex vesicarius methanol extract
  154. Chemical compositions of Litsea umbellata and inhibition activities
  155. Green synthesis, characterization of silver nanoparticles using Rhynchosia capitata leaf extract and their biological activities
  156. GC-MS analysis and antibacterial activities of some plants belonging to the genus Euphorbia on selected bacterial isolates
  157. The abrogative effect of propolis on acrylamide-induced toxicity in male albino rats: Histological study
  158. A phytoconstituent 6-aminoflavone ameliorates lipopolysaccharide-induced oxidative stress mediated synapse and memory dysfunction via p-Akt/NF-kB pathway in albino mice
  159. Anti-diabetic potentials of Sorbaria tomentosa Lindl. Rehder: Phytochemistry (GC-MS analysis), α-amylase, α-glucosidase inhibitory, in vivo hypoglycemic, and biochemical analysis
  160. Assessment of cytotoxic and apoptotic activities of the Cassia angustifolia aqueous extract against SW480 colon cancer
  161. Biochemical analysis, antioxidant, and antibacterial efficacy of the bee propolis extract (Hymenoptera: Apis mellifera) against Staphylococcus aureus-induced infection in BALB/c mice: In vitro and in vivo study
  162. Assessment of essential elements and heavy metals in Saudi Arabian rice samples underwent various processing methods
  163. Two new compounds from leaves of Capparis dongvanensis (Sy, B. H. Quang & D. V. Hai) and inhibition activities
  164. Hydroxyquinoline sulfanilamide ameliorates STZ-induced hyperglycemia-mediated amyleoid beta burden and memory impairment in adult mice
  165. An automated reading of semi-quantitative hemagglutination results in microplates: Micro-assay for plant lectins
  166. Inductively coupled plasma mass spectrometry assessment of essential and toxic trace elements in traditional spices consumed by the population of the Middle Eastern region in their recipes
  167. Phytochemical analysis and anticancer activity of the Pithecellobium dulce seed extract in colorectal cancer cells
  168. Impact of climatic disturbances on the chemical compositions and metabolites of Salvia officinalis
  169. Physicochemical characterization, antioxidant and antifungal activities of essential oils of Urginea maritima and Allium sativum
  170. Phytochemical analysis and antifungal efficiency of Origanum majorana extracts against some phytopathogenic fungi causing tomato damping-off diseases
  171. Special Issue on 4th IC3PE
  172. Graphene quantum dots: A comprehensive overview
  173. Studies on the intercalation of calcium–aluminium layered double hydroxide-MCPA and its controlled release mechanism as a potential green herbicide
  174. Synergetic effect of adsorption and photocatalysis by zinc ferrite-anchored graphitic carbon nitride nanosheet for the removal of ciprofloxacin under visible light irradiation
  175. Exploring anticancer activity of the Indonesian guava leaf (Psidium guajava L.) fraction on various human cancer cell lines in an in vitro cell-based approach
  176. The comparison of gold extraction methods from the rock using thiourea and thiosulfate
  177. Special Issue on Marine environmental sciences and significance of the multidisciplinary approaches
  178. Sorption of alkylphenols and estrogens on microplastics in marine conditions
  179. Cytotoxic ketosteroids from the Red Sea soft coral Dendronephthya sp.
  180. Antibacterial and biofilm prevention metabolites from Acanthophora spicifera
  181. Characteristics, source, and health risk assessment of aerosol polyaromatic hydrocarbons in the rural and urban regions of western Saudi Arabia
  182. Special Issue on Advanced Nanomaterials for Energy, Environmental and Biological Applications - Part II
  183. Green synthesis, characterization, and evaluation of antibacterial activities of cobalt nanoparticles produced by marine fungal species Periconia prolifica
  184. Combustion-mediated sol–gel preparation of cobalt-doped ZnO nanohybrids for the degradation of acid red and antibacterial performance
  185. Perinatal supplementation with selenium nanoparticles modified with ascorbic acid improves hepatotoxicity in rat gestational diabetes
  186. Evaluation and chemical characterization of bioactive secondary metabolites from endophytic fungi associated with the ethnomedicinal plant Bergenia ciliata
  187. Enhancing photovoltaic efficiency with SQI-Br and SQI-I sensitizers: A comparative analysis
  188. Nanostructured p-PbS/p-CuO sulfide/oxide bilayer heterojunction as a promising photoelectrode for hydrogen gas generation
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