Bulletin of the Chemical Society of Ethiopia

Ultrasonication and RSM-based optimization of antioxidant activity, saccharide composition and fatty acids from Phoenix dactylifera L. Medjool date seeds influenced by ethanol

2024-03-12T08:10:16+00:00

In response with the demand in date industry finding on sustainable solution for date seeds management and its bioactive rich constituent, current study envisaged the optimum condition for the ultrasound extraction of Phoenix dactylifera L. Medjool date seeds and its antioxidative activity by employing a three-level three-factor Box–Behnken design via response surface methodology (RSM). Ethanol (EtOH) concentration (50-80%), time (30-90 min) and temperature (40-70 °C) were the independent variables investigated for ABTS^•+ scavenging antioxidant activity and subjected to analysis of variance (ANOVA). The optimum conditions for maximum antioxidant activity (60.93% ± 0.021) were achieved at 80% EtOH, 44 min and at 57 °C, where the effect of EtOH concentration were notably significant. The observed agreement between the experimental (60.93% ± 0.021) and predicted (60.35%) values indicated the employed model suitability while substantiates the successful implementation of RSM for optimizing extraction parameters. The optimized extract characterized through UPLC-QTOF/MS and GC-MS/MS, detailed the presence of saccharides (isomaltose, mannotriose and stachyose) and volatile compounds, namely 5 saturated fatty acids that encompassed within the 8.42% (w/w) of total fat obtained. This verifies the ability of the solvent mixture extracting fatty acids and saccharides even under high EtOH concentration.

KEY WORDS: Date seeds, Response surface methodology (RSM), Antioxidant, Saccharide, GC-MS/MS, UPLC-QTOF/MS

Bull. Chem. Soc. Ethiop. 2024, 38(3), 547-562.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.1

Wax screen-based fabrication of paper devices for the determination of iron in particulates of selected welding fumes in Addis Ababa, Ethiopia

2024-03-12T08:20:29+00:00

In this study a paper-based analytical device was developed using screen printing technique for the determination of particulate iron from welding fumes. The operational parameters such as volume and concentration of 1,10-phenanthroline, volume and concentration of hydroxylamine were optimized by the Box Behnken Design (BBD) using Minitab. Additionally, the µ-PAD's sample solution holding capacity and reaction time were also optimized. Under the optimized condition, particulate metal concentrations were colorimetrically quantified using
a handheld mobile phone and image processing software, ImageJ. Very good analytical performance such as good linearity of the calibration curve and better selectivity was observed by the developed method. The limit of detection for Fe³⁺ assay was 4.6 mg/L; which is adequate to determine the threshold concentration limit of particulate iron set by the regulatory bodies (6 mg/L). The µ-PAD revealed 95-99% recovery compared with the UV-Vis spectrophotometry (98-100%). Furthermore, welding fume samples were collected in Addis Ababa over five days, using mixed cellulose ester filters and the findings show a high concentration that exceeds the standard levels. Analyzing particulate iron with µ-PADs yielded results consistent with UV-Vis spectrophotometry, suggesting µ-PADs' potential application for occupational particulate iron exposure measurement, eliminating the need for expensive analytical devices.

KEY WORDS: µ-PADs, Particulate iron, Response surface methodology, Wax screen-printing, Welding fume, Colorimetric detection

Bull. Chem. Soc. Ethiop. 2024, 38(3), 563-576.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.2

Spectrophotometric determination of amoxicillin in pharmaceutical formulations using normal and reverse flow injection analysis systems: A comparison study

2024-03-12T08:26:23+00:00

The combination of flow injection technique and spectrophotometric detection can be employed for the rapid and low-cost methods for antibiotic assay. In this work, two flow injection analysis (FIA) systems, normal and reverse (nFIA and rFIA), combined with UV-Vis spectrophotometric technique were used for amoxicillin determination in its pure and pharmaceutical preparations. A colorimetric coupling reaction between amoxicillin and diazotized p-toluidine produced a bright yellow azo dye and quantified at a maximum wavelength of 426 nm. For nFIA and rFIA procedures, the amoxicillin calibration graphs had an RSD of less than 2% and were linear in the ranges of 5-200 and 1-140 µg/mL, respectively. The limits of detection and quantification were 1.41 and 4.71 µg/mL of amoxicillin for nFIA and 0.39 and 1.31 µg/mL for rFIA, respectively. The physical and chemical factors that could influence color sensitivity were investigated. Various commercial formulations containing different amounts of amoxicillin were successfully tested using the developed approaches, which demonstrated to be easy, rapid, reproducible, and interference-free.

KEY WORDS: Amoxicillin, Normal FIA, Reverse FIA, p-Toluidine, Diazotization reaction

Bull. Chem. Soc. Ethiop. 2024, 38(3), 577-590.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.3

A spectrophotometric determination and the quantum chemical investigation of Pd(II)-3-hydroxy-2-(4-methoxyphenyl)-4-oxo-4H-1-benzopyran complex

2024-03-12T08:30:50+00:00

An analytical approach has been instigated for spectrophotometric inquisition of trace amounts of palladium in its bivalent oxidation state employing a novel 1-benzopyran derivative viz. A 1:2 [Pd(II):HMPB] light yellow complex is formed by a spontaneous interaction between Pd(II) and HMPB. The complex is quantitatively extracted from a weakly basic medium into dichloromethane absorbing prevalently and consistently at 405-425 nm. The method coheres to linearity up to 1.5 µg mL^-1 of palladium(II). Analytical parameters such as the molar absorption coefficient (ε=3.011 × 10⁴ L mol^-1 cm^-1), Sandell's sensitivity [0.0035 µg Pd(II) cm^-2], % RSD (0.62%) and the limit of detection [0.0147 µg Pd(II) mL^-1] indicate that the study satisfies all the criteria for good sensitivity, precision and accuracy. In addition, intervention with regard to numerous anions/complexing agents and cations of primary analytical importance has been performed to assess the method's flexibility and usefulness. The results show that the majority of them do not cause any interference during determination. To better understand chemistry of the prepared complex, spectroscopic quantum chemical studies including DFT and MEP mapping based on examination of the electronic characteristics of the complex in its most stable least energy conformation are used.

KEY WORDS: Palladium, 3-Hydroxy-2-(4-methoxyphenyl)-4-oxo-4H-1-benzopyran, Extractive spectrophotometric determination, DFT, MEP, Docking

Bull. Chem. Soc. Ethiop. 2024, 38(3), 591-603.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.4

Synthesis, characterisation, and anticancer and antioxidant activities of novel complexes of palladium and an organic Schiff-base ligand

2024-03-12T08:40:50+00:00

Treatment of the Schiff base 2-N-(salicylidene) benzothiazole (SabtH) with palladium chloride afforded the neutral 2-N-(salicylidene) benzothiazole palladium(II) complex. This was then treated with one molar equivalent of either ethylenediamine or 1,10-phenanthroline, yielding the neutral mixed ligand complexes 1 and 2, respectively. The prepared organic ligand and its mixed ligand complexes were characterised via UV-Vis, FTIR, ¹H-NMR, and ¹³C-NMR spectroscopy. The antiproliferative activities of 1 and 2 were tested against MCF-7 (breast) and HT-29 (colon) cancer cells using an MTT assay. 1 showed strong antiproliferative activity against both MCF-7 and HT-29 cancer cells, with IC₅₀ values of 74.6 ± 8.35 and 174 ± 20.28 µg/mL, respectively. In addition, 2 exhibited the maximum antioxidant activity, with an EC₅₀ value of 1029 ± 196.76 µg/mL.

KEY WORDS: 2-N-(Salicylidene) benzothiazole, 1,10-Phenanthroline, Palladium mixed ligand complexes, Anticancer, Antioxidant activity

Bull. Chem. Soc. Ethiop. 2024, 38(3), 605-613.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.5

Experimental and rheological modelling on the stabilization of iron ore slurry using a biosurfactant extracted from Aloe barbadensis Miller

2024-03-12T08:45:10+00:00

The pipeline transportation of iron ore slurry (IOS) is an eco-friendly alternate mode to transport the raw materials to longer distance and reduce the transportation network congestion problems. Proper selection of surfactant could modify mineral’s viscosity, dispersion and wetting characteristics effectively as may be desired, which may further be monitored. A surfactant alters surface characteristics after being adsorbed onto minerals by altering the interfacial behaviour. This work is first report of the influence of a biosurfactant sourced from Aloe barbadensis Miller on the rheological behaviour of a high-grade iron ore (IO) sample at 45–72% by mass slurry concentrations range. The observed rheological parameters confirmed the non-Newtonian flow behaviour of the slurry. The collected IO and dried IOS samples were subjected to UV-Vis, XRF, PSD, XRD, SEM and EDS analyses. Experimental rheological data at varying concentrations was tested on various models to ascertain the best-fit rheological model for IOS transport. The Bingham model was found to be the most suitable to model the rheology of IOS. Experimental rheological behaviour of IOS was found to be linear with the yield stress. The study shall help to ascertain the suitability of a biosurfactant to stabilise high grade iron ores for pipeline transportation.

KEY WORDS: Iron ore slurry, Aloe barbadensis, Rheological measurements, Rheological modelling

Bull. Chem. Soc. Ethiop. 2024, 38(3), 615-629.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.6

Prolific application of green synthesised CdS nanoparticles for the sequestration of cationic dyes from aqueous solution

2024-03-12T08:49:37+00:00

Synthesis of cadmium sulfide (CdS) nanoparticles using watermelon rind aqueous extract was explored for its effectiveness in eliminating Methylene Blue (MB) and Crystal Violet (CV) dyes from water. The synthesised CdS nanoparticles were characterised with XRD, TEM and EDX and found to be around 10 nm in size with spherical shape. A central composite design was developed to optimise independent variables such as pH, contact time and initial concentrations. The developed quadratic model was found to be significant with p-value <0.0001 and lack of fit >0.005 suggesting the reliability of the model. Isotherm modelling analysis revealed that Langmuir and Freundlich's isotherms provided better explanation for the equilibrium data. The loading capacities of the CdS nanoparticles were found be 227.3 and 185.1 mg g^-1, respectively for MB and CV. The experimental data showed a good fit with the pseudo-second-order kinetic model, indicating that chemical reactions were the determining factor in controlling the rate-limiting step. Thermodynamic analyses indicated that the process was spontaneous and exothermic. Desorption and regeneration investigations demonstrated that CdS nanoparticles could be successfully regenerated up to 5 times and reused in the adsorption process. The results conclude that the CdS nanoparticles are capable of remediating water containing cationic dyes.

KEY WORDS: Watermelon rind, CdS nanoparticles, Synthetic dyes, Adsorption, RSM

Bull. Chem. Soc. Ethiop. 2024, 38(3), 631-645.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.7

Boosted antibacterial efficacy: Di and triorganotin complexes via 2-[(2,3-dimethylphenyl)amino]benzoic acid

2024-03-12T09:06:28+00:00

Using appropriate organotin chloride salts and a ligand called 2-[(2,3-dimethylphenyl) amino] benzoic acid (DMPAB), a condensation procedure produced novel complexes such as triphenyltin, dimethyl, diphenyl, and dibutyl-tin. For difficult identification, a variety of analytical methods were used, including elemental analysis, carbon and proton magnetic resonance, and infrared spectra. The agar ditch method was used to assess the antibacterial effectiveness against Staphylococcus aureus and Escherichia coli. When compared to the molecule generated from the ligand, the complexes showed more inhibitory action. Among the complexes tested, the dimethyltin carboxylate complex showed the strongest antibacterial action against Staphylococcus aureus and Escherichia coli.

KEY WORDS: Complexes, Antibacterial properties, Condensation process, Agar Ditch, Staphylococcus aureus and Escherichia coli

Bull. Chem. Soc. Ethiop. 2024, 38(3), 647-655.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.8

Nickel oxide nanoparticles as sustainable catalysts for efficient synthesis and anti-microbial evaluation of 2-amino-4H-pyran derivatives

2024-03-12T09:10:14+00:00

In the current paper, nickel oxide nanoparticles (NiO NPs) was successfully applied as a sustainable effective and recoverable catalyst for the preparation of 2-amino-4H pyran derivatives 2-11 via one-pot, three-component reaction of 4-formylphenyl-4-methyl benzenesulfonate (1) with malononitrile and active methylene compounds in green solvent water and ethanol in ratio (3:1) in excellent yield (95-98%) and shorter reaction time (5-8 min). The structures of the pyran derivatives were elucidated by elemental and spectral analyses such as IR, ¹H NMR, ¹³C NMR and DEPT 135 spectra. Moreover, the characterization of the catalyst after and before the reaction were studied using X-ray diffraction (X-RD), scanning electron microscope (SEM), EDX techniques and IR-spectra. It has been indicated that catalyst has the same efficiency. The application of this protocol has many advantages such as eco-friendly, inexpensive, simple protocol and easy recovery of the catalyst. Overall products are designed, synthesized and studied for their anti-microbial evaluation. It has been found that is compounds 2, 3, 7 and 10 are the most active against antibacterial compression with the stander drug Ampicillin. On the other hand, Compounds 2, 3, 8, and 11 displayed the most promising antifungal activities with Amphotericin B.

KEY WORDS: Nickel oxide nanoparticles, Pyran derivatives, X-Ray diffraction (X-RD), Antimicrobial evaluation, One-pot, Three-component reaction

Bull. Chem. Soc. Ethiop. 2024, 38(3), 657-670.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.9

Preparation, spectroscopic and anticancer investigations of metal-drug complexes associated between flumequine antibiotic drug with lanthanum(III), samarium(III) and terbium(III) chloride

2024-03-12T09:21:56+00:00

Flumequine ligand (FLQ) metal complexes of the [M(FLQ)₂(Cl)(H₂O)].nH₂O type, where M are (La(III), Sm(III), and Tb(III)) and FLQ is flumequine have been synthesized. The FLQ metal complexes could be prepared using MCl₃ : flumequine in stoichiometry of 1:2 in situ bidentate chelation. The characterization of FLQ complexes obtained have been done using elemental analyses (%C, %H and %N), molar conductivity (Ʌ_m), infrared spectroscopy (FTIR), electronic spectra (UV-Vis), thermal analysis (TGA), and physicochemical techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) measurements at room temperature. Accordingly, these complexes are indicative of an octahedral coordination structure. Flumequine ligand has a bidentate fashion through the oxygen atoms of carbonyl (quinolone) and carboxylic groups. The findings demonstrated the anti-cancer efficacy of these compounds against HepG-2 and MCF-7 cancer cell lines at extremely low doses of up to 58.2 mg/mL. The La(III) complex was shown to have the highest selectivity against cancer cells in comparable with both samarium and terbium(III) complexes.

KEY WORDS: Flumequine, Lanthanide metal ions, FTIR, EDX, Complexation, Anticancer activity

Bull. Chem. Soc. Ethiop. 2024, 38(3), 671-684.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.10

Enoxacin fluoroquinolone antibacterial agent complexes with Pt(IV), Ru(III) and Ir(III) ions: Synthesis, spectroscopic, physicochemical characterizations and biological studies

2024-03-12T09:28:41+00:00

The synthesis, physicochemical characterizations, and biological investigations on the chelation of the antibiotic medication enoxacin (EXN) with certain vital metal ions, such as platinum(IV), ruthenium(III), and iridium(III) are discussed in this study. These compounds structures were interpreted based on elemental analysis and spectral measurements (FTIR, ¹H-NMR, UV-Vis electronic, and XRD). The findings show that there is same coordination pathway for the chelation behavior of enoxacin complexes: a monodentate manner. The Pt(IV), Ru(III), and Ir(III) complexes are coordinated through the N atom of the piperazine ring, which is an unusual mode of coordination for this class of compounds. The dissolved complexes in DMSO were found to have non-electrolyte nature based on their molar conductance measurements. The formula for these complexes is [Pt(EXN)₃(H₂O)₂Cl] (1), [Ru(EXN)₃(H₂O)₃] (2), and [Ir(EXN)₃(H₂O)₃] (3). Using scanning electron microscope (SEM) analysis and X-ray powder diffraction (XRD), the nano-scale range of the Pt(IV), Ru(III), and Ir(III) complexes has been determined. Results of in vitro cytotoxicity were examined using MCF-7 cells (human breast cancer cell line) and HepG-2 cells (human hepatocellular carcinoma) that had been grown. The cytotoxic activity of the metal complexes demonstrated a cytotoxic effect against the growth of human breast and liver cancer cell lines.

KEY WORDS: Enoxacin, Platinum(IV), Complexity, Spectral analyses, Biological assessments

Bull. Chem. Soc. Ethiop. 2024, 38(3), 685-699.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.11

Synthesis, spectroscopic characterizations and biological studies on gold(III), ruthenium(III) and iridium(III) complexes of trimethoprim antibiotic drug

2024-03-12T09:31:10+00:00

Ruthenium(III), gold(III), and iridium(III) trimethoprim drug (TMP) complexes were synthesized and analyses via microanalytical approach (C, H, N analysis), magnetic, molar conductance, and FTIR, ¹H NMR, XRD, and UV-Vis spectroscopy. Through two nitrogen atoms of –NH₂ amino groups, the TMP drug coordinated as a bidentate ligand towards the corresponding three metal ions. The geometrical structure of the compounds ruthenium(III), gold(III), and iridium(III) is octahedral and consists of two TMP molecules, two coordinated chlorine atoms, and one uncoordinated chlorine atom. The antibacterial properties of TMP complexes have been investigated through the use of many bacterial species, including Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. Additionally, the generated complexes' anticancer properties against HepG-2 (human hepatocellular carcinoma) and MCF-7 (human breast cancer cell line) have been assessed. In contrast to those of clinically used antibiotics, the inhibition zone of ruthenium and iridium(III) complexes was in the low efficiency range, and the antibacterial activity of gold(III) complexes was moderate. This article discusses the possibilities and prospects for this family of metallodrugs as antibacterial or anticancer medicines.

KEY WORDS: Trimethoprim drug, Chelation, Gold, TEM, XRD, FTIR

Bull. Chem. Soc. Ethiop. 2024, 38(3), 701-714.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.12

Synthesis and characterization of silver nanoparticles from Cocos nucifera L. male flowers: An investigation into their potent antibacterial and anticancer efficacy

2024-03-12T09:33:43+00:00

The current research focused on the production of silver nanoparticles using dichloro methane-mediated Cocos nucifera male flower extract and their minimum inhibitory concentration against ten different bacterial pathogens. C. nucifera male flowers were extracted by 100% DCM, and the phytochemicals present in this extract were studied. These plant phytochemicals act as reducing agents to reduce the silver nitrate (AgNO₃) to silver nanoparticles (AgNPs) which was confirmed by UV/Vis spectrophotometer, Fourier transform infra-red spectrum, X-ray diffraction analysis, and scanning electron microscopy. The 15 µL of silver nanoparticles was the minimum inhibitory concentration for Klebsiella pneumonia and Bacillus subtilis. The 20 µL of silver nanoparticles is the MIC for Pseudomonas aeruginosa, Vibrio harveyi, and Plesiomonas shigelloides. 30 µL of plant flower extract concentration highly inhibits the E. coli, Staphylococcus aureus, Salmonella paratyphi, Vibrio mimicus, and Vibrio alginolyticus bacterial pathogens. C. nucifera male flowers extract derived silver nanoparticles are highly stable and have high potential activity against MCF-7 Cell line.

KEY WORDS: Cocos nucifera, Nanoparticles, Phytochemicals, Antimicrobials, Bacterial pathogens, MCF 7 Cell line

Bull. Chem. Soc. Ethiop. 2024, 38(3), 715-724.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.13

Synthesis, spectroscopic and biological characterizations of platinum(IV), ruthenium(III) and iridium(III) theophylline complexes

2024-03-12T09:36:53+00:00

This study used micro-analyses, (FTIR, UV-Vis) spectra, magnetic, thermogravimetric, X-ray powder diffraction (XRD) patterns, and transmittance electron microscopy (TEM) techniques to characterize three synthesized theophylline (TPH) complexes with ruthenium(III), platinum(IV), and iridium(III) metal ions. The metal ions indicated above were found to align with the TPH drug chelate as a mono-dentate ligand via the deprotonated NH group at the nitrogen atom position N7, as verified by FTIR measurements. Additionally, the complexes conductivity and magnetic susceptibility were examined. The octahedral geometry for the synthesized complexes was proposed by the current data. Except for the iridium(III) complex, which has a non-electrolytic nature due to the presence of a chlorine atom inside the chelation sphere, the molar conductivity of the complexes in DMSO solution was electrolyte in nature. Theophylline complexes with a (metal: ligand) stoichiometry of 1:2 were produced. The TPH complexes have also been tested in vitro against G(+) bacteria (Bacillus subtilis and Staphylococcus Aureus) and G(-) bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate their antibacterial efficacy. Human breast and liver cancer cell lines were used as a test for the TPH complexes in vitro anti-cancer properties.

KEY WORDS: Theophylline, Metal ions, Chelation, Octahedral, Spectral analysis, Nano-particles, Biological evaluation

Bull. Chem. Soc. Ethiop. 2024, 38(3), 725-738.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.14

Multicomponent reactions of cyanoacetanilide derivatives: Synthesis of coumarin and quinoline derivative and evaluations of their cytotoxicity

2024-03-12T09:44:13+00:00

In this study, several fused heterocyclic systems involving tetrahydrobenzopyrans 7a-i and tetrahydrobenzopyridines 9a-i were synthesized. The reactions proceed via a multicomponent reaction of different aromatic aldehydes, cyanoacetanilide derivatives, and cyclohexane-1,3-dione. All the produced compounds were tested for their anticancer activity by using six cancer cell lines such as A549, HT-29, MKN-45, U87MG, SMMC-7721 and H460 utilizing foretinib as the positive control and the standard MTT assay in vitro. The results indicated that many synthesized derivatives were the most potent towards all the cancer cell lines used, six compounds 7e, 7f, 9b, 9d, 9e, and 9g showed the highest potency. The results obtained in this work enhance further investigations in the future.

KEY WORDS: Multi-component reactions, Cyanoacetanilide, Pyran, Pyridine, Cytotoxicity

Bull. Chem. Soc. Ethiop. 2024, 38(3), 739-750.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.15

Hepatoprotective perspective of newly synthesized 3-(3,5-bis (tri fluoro methyl) phenyl)- 5-methyl-1-((1-methyl-1h-pyrrol-2-yl) methyl)-2-thioxoimidazolidin-4-one against diethyl nitrosamine induced liver injury in rats with molecular docking investigatio

2024-03-12T09:49:51+00:00

The hepatoprotective effect of synthesized 3-(3,5-bis (trifluoromethyl) phenyl)-5-methyl-1-((1-methyl-1H-pyrrol-2-yl) methyl)-2-thioxoimidazolidin-4-one (3FL-M) was evaluated against diethyl nitrosamine-induced liver injury (DEN). Wistar rats were divided into 3 groups as: placebo (received 10% tween 80%), hepatotoxic control (injected with 200 mg/kg of DEN) and treatment (injected 200 mg/kg of DEN and received 50 mg/kg oral feeding of the synthesized 3FL-M). Half the number of the rats were sacrificed on 2^nd week of the experiment, whereas the other half were sacrificed after 6 weeks. Blood was collected to run liver biochemical analysis, and to evaluate pro-inflammatory cytokines tumor necrosis factor-alpha TNF-α and interleukine6 IL-6. Liver sections were used to detect nuclear protein ki-67 and hepatocyte specific antibody HSA. 3FL-M was subjected to molecular docking calculations based on binding affinities towards TNF-α and IL-6. DEN-treated rats showed elevation in the liver serum enzymes as well as pro-inflammatory cytokines with clear destruction of the hepatic architecture, in contrast 3FL-M treated rats showed normalized liver enzymes and cytokines levels with resolution of the hepatocytes. Molecular modelling revealed that 3FL-M exhibited the significant affinities toward the binding pocket of the TNF-α and IL-6, however, further studies is recommended for developing it as a chemotherapeutic drug-like molecule.

KEY WORDS: DEN, Hepatoprotective, TNF-α, IL-6, Molecular docking

Bull. Chem. Soc. Ethiop. 2024, 38(3), 751-763.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.16

Design, synthesis of novel Schiff bases as potential insecticidal agents against Spodoptera frugiperda (Lepidoptera: Noctuidae)

2024-03-12T09:55:10+00:00

In the present work, novel series of Schiff base 2-7 were synthesized via treatment of p-tosyloxy benzaldehyde with some indole and quinoxaline derivatives in ethanol under reflux. All product structures were verified using elemental analysis and spectroscopic investigations, including ¹³C NMR, ¹H NMR, and IR. Our research was conducted on the insecticidal activity, and biological effects of the recently synthesized Schiff bases on S. frugiperda. The results showed that compound 5 was the most active insecticide, nearly surpassing methomyl as a reference, with LC₅₀ values of 46.35 mg/L for second-instar larvae and 97.37 mg/L for fourth-instar larvae. This research opened up new avenues for the search for a novel class of insecticide.

KEY WORDS: Schiff bases, Spodoptera frugiperda, Insecticidal activity, Biological aspects, Toxicity

Bull. Chem. Soc. Ethiop. 2024, 38(3), 765-774.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.17

New approaches for the synthesis of chromene and quinoline derivatives and their anti-proliferative, morphological studies

2024-03-12T10:01:32+00:00

This work aimed to evaluate the anticancer potential of the novel 5,6,7,8-tetrahydro-4H-chromenes against selected six cancer cell lines together with the prostate cancer cell line PC-3. A novel series of substituted 5,6,7,8-tetrahydro-4H-chromenes were synthesized through feasible synthetic strategy. The synthetic schemes involve firstly the multi-component reactions of dimedone with the aromatic aldehydes and ethyl acetoacetate to produce the 5,6,7,8-tetrahydro-4H-chromenes derivatives. On the other hand, carrying the same reactions using NH₄OAc produced the hexahydroquinoline compounds. Anti-proliferative evaluations and inhibitions for all synthesized compounds toward selected cancer cell lines were carried out and the results revealed that many of them exhibited high inhibitions. Morphology of A549 cell line by the effect of compounds 14f and 16c was performed.

KEY WORDS: Anti-proliferative activity, Chromene derivatives, Morphology, Multi-component reactions

Bull. Chem. Soc. Ethiop. 2024, 38(3), 775-798.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.18

Thermodynamic modeling of the solid-liquid equilibrium of two phenolic compounds in several solvents at temperatures ranging from 283.15 K to 323.15 K

2024-03-12T10:04:37+00:00

The solubility of two natural phenolic compounds (vanillic acid (VA) and vanillin (V)) in four individual solvents (ethanol, butan-2-ol, ethylene glycol, and ethyl acetate) was measured using the gravimetric method from 283.15 to 323.15 K at atmospheric pressure. The optimization of the complexes between VA–solvents and V–solvents using the B3LYP theoretic technique and the 6-31+G (d, p) basis set indicated that the absolute value of interaction energy was higher, suggesting that the interaction between solute and the solvent was stronger. In addition, two excellent activity coefficient models (NRTL and Wilson) were used to correlate and evaluate the equilibrium solubility results. The highest relative average deviation and root-mean-square deviation values for VA are 4.36% and 3.09 × 10^-3, respectively, and 3.35% and 5.52 × 10^-3 for V. Furthermore, the excess enthalpy of the solution was determined on the basis of thermodynamic relations and the Wilson model. The findings indicate that the dissolution process was endothermic.

KEY WORDS: Solid-liquid equilibrium, Vanillin, Vanillic acid, NRTL and Wilson models, Thermodynamic parameters

Bull. Chem. Soc. Ethiop. 2024, 38(3), 799-810.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.19

Corrosion and inhibition studies on AISI 316 with AISI 410 fiber laser welded joints

2024-03-12T10:07:44+00:00

In this investigation, the corrosion study was conducted on fiber laser welded joints of AISI 410 and 316L stainless steel plates using hydrochloric acid, basic, and salt medium, behavior in three different pH. The effects of three different corrosive atmospheres were examined using the weight loss method. The test sample which was exposed to 1 N hydrochloric acid medium for 48 Hours resulted in 0.006 g of weight loss. The maximum amount of corrosion was found in the acidic medium whereas the least was observed in the salt medium. The effectiveness of three distinct derivatives of 1H-indole-2,3-dione, each replaced with hydroxyl groups in various positions, in inhibiting corrosion. Among the three derivatives examined, it was observed that those with ortho and para hydroxyl group substitutions exhibited superior inhibitory properties.

KEY WORDS: Fiber laser welding, Traverse speed, Corrosion study, Isatin Schiff base, Inhibitors

Bull. Chem. Soc. Ethiop. 2024, 38(3), 811-823.

DOI: https://dx.doi.org/10.4314/bcse.v38i3.20