Abstract: Using zooplankton as bioindicators, this study evaluates the ecological condition of the Euphrates River in Iraq's Babylon Province. Site 1 (North Hillah, next to the old Babylon ruins), Site 2 (Hillah city center), Site 3 (South Hillah, close to Al-Mahaweel), and Site 4 (near Al-Kifl town) were the four monitoring locations chosen along the river. The highest and lowest averages of the measured physical and chemical factors indicate temperature (25.1°-29.4°), pH (7.2-7.9), electrical conductivity (EC) (940 µS/cm-1241µS/cm), total dissolved solids TDS (591 mg/L-789mg/L), dissolved oxygen (DO) (5.6 mg/ l-7.1 mg/L), biological oxygen demand (BOD5) (2.4mg/L-4.2 mg/L), nitrate (1.3 mg/L–3.2 mg/L), nitrite (0.04 mg/L–0.13 mg/L), phosphate (0.3 mg/L-0.6 mg/L), turbitity (5.5 NTU-9NTU), calcium (45 mg/L-60 mg/L), magnesium (20 mg/L–35 mg/L), total hardness (150 mg/L–210 mg/L) that was the seasonal data for the year. Zooplankton communities were collected include amphipoda (52 ind/l-116 ind/L), cladocera (68 ind/l-114 ind/L), cyclopodia (154 ind/L-350 ind/L), macrobrachium nipponense (224 ind/L-350 ind/L), decapoda (Crab) (54 ind/L-112ind/L), Naplus larvae (16 ind/L-76 ind/L), and analyzed for diversity indices recorded including shannon-Wiener index (1,499-1.719), species richness according to 6 in all locations species evenness between (0.837-0.96). The Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was applied to evaluate the water quality and he recorded between (45.16-72.42). According to the study, the water quality of babylon's euphrates river ranges from poor to fair. Although they varied by location and season, the physical, and chemical conditions were generally within tolerable bounds. There were six major groupings of zooplankton, indicating a moderate level of diversity. Aquatic life is generally supported by the river, although certain locations exhibit indications of ecological stress.

Abstract: In the current study, the DFT and TD-DFT methods are used to investigate seven donor–π-acceptor (D–π–A) dyes, named DY01 to DY07, which are planned for utilization in DSSCs. The HOMO-LUMO gaps are decreased due to the solvent effect by 0.05-0.16 eV and are smallest (1.85 eV) for DY01. Frontier molecular orbitals show that charge separation is efficient between triphenylamine donor and cyanoacrylic acid acceptor. The bathochromic shift due to the solvent effects is estimated by the TD-DFT calculations, and DY01 exhibits the maximum red shift (638 nm) as well as DY05 has the highest oscillator strength (f = 1.664). Photovoltaic parameters reveal that DY01 is the most efficient (0.958), and DY02 could receive the relatively better electrons injection strength accompanied with high Voc value. Adsorption on (TiO₂)₈ cluster has an additional decrease the energy gaps and DY01 and DY07 show strong red shifts. Upon adsorption, the orbital distribution shows strong electronic coupling conducive to photo-induced electron transfer to the semiconductor. It can be concluded that DY01 is the most efficient sensitizer showing highest quantum efficiency due to its narrow band gap, effective intramolecular charge transfer (ICT), high light-harvesting efficiency (LHE) and favorable interfacial properties.

Abstract: Attempts to synthesize N-phenyl-2-((5-phenyl-4H-1,2,4-triazol-3-yl)thio)acetamide was unsuccessful via cycloaddition reaction between the N-phenyl-2-thiocyanatoacetamide and benzohydrazide in the presence of Lewis acid. During this procedure, a side product, 2-(phenylamino)thiazol-4(5H)-one is obtained through intramolecular cyclization. However, nucleophilic substitution reactions performed between 5-phenyl-4H-1,2,4-triazole-3-thiol and 2-chloro-N-arylacetamides in the presence of K₂CO₃ yielded a series of 4H-1,2,4-triazole-tethered acetamides in aqueous medium. The procedure affords excellent yields of desired products containing electron-withdrawing and electron-donating groups on the aromatic rings in a short reaction time with ease of operation. The oxidation potential and photocurrent measurements of the targets indicated that the presence of the electron-withdrawing substituents afforded better results with a lower oxidation potential and higher photocurrent measurements.

Supplementary data PDF (4600 K)

Abstract: This comprehensive review explores the dual facets of pesticides, emphasizing their critical role in enhancing agricultural productivity and disease control while addressing their associated environmental and health risks. It examines the benefits of pesticide use, including increased crop yields, protection against pests and disease vectors, and economic advantages. Conversely, it highlights the potential adverse effects such as environmental contamination, biodiversity loss, resistance development, and human health concerns. The review advocates for sustainable pest management strategies, including integrated pest management and innovative alternatives, to balance the benefits with the pressing need for environmental and public health protection.

Abstract: This paper presents the results of a search for inhibitors targeting the SARS-CoV-2 Mpro and PLpro proteases, which are crucial enzymes involved in viral replication. The development of new molecules designed as dual non-covalent inhibitors of these proteases was based on previous research that identified a lead compound: N-phenyl-2-(7-oxo-8-(phenylaminomethyl)-2,3-dihydro-[1,4]dioxino[2,3-g]quinolin-6(7H)-yl)acetamide. This compound showed high affinity for the active sites of both Mpro and PLpro in in silico modeling. Using this lead structure as a foundation, we optimized the scaffold by introducing various substituents to create a targeted compound library. We quantitatively analyzed the relationships between the contributions of these substituents and their molecular affinity for the protease active sites. This analysis helped us identify specific substituents that enhanced interactions with both biological targets and suggest a series of 17 modified derivatives, which show promise as dual inhibitors of M^pro and PL^pro. According to docking studies, all synthesized compounds demonstrated favorable interactions within the catalytic sites of both proteases. Moreover, we found that hit-ligands 7d and 7f exhibit binding scores of -9.0 kcal/mol, which are comparable to, or even higher than, those of the reference ligands WU-02 for Mpro and XR8-89 for PLpro, respectively. We successfully implemented the proposed synthetic schemes, allowing us to prepare novel compounds for subsequent in vitro evaluation.

Supplementary data PDF (4600 K)

Abstract: Condensed bicyclic systems with 1,3,4-thiadiazole core being annulated to pyridine or pyrimidine ones occupy prominent place in medicinal chemistry because of their broad spectrum of pharmacological properties. The combination of these heterocyclic systems into a bicyclic scaffold commonly provides much more interest in the enhanced activity profile of its analogs than their parent monocyclic constituents. Thus, a number of pyridines or pyrimidines fused to thiadiazoles are incorporated into a wide variety of therapeutically important compounds possessing a broad spectrum of biological activities. In the present review we highlight recent advances in the fast-growing research area of thiadiazolo[3,2-a]pyridines and thiadiazolo[3,2-a]pyrimidines chemistry summarizing the existing literature information with respect of their synthetic approaches. Considering such a significant pharmacological potential, as well as wide synthetic possibilities, mentioned fused heterosystems have received considerable attention from scientific community as perspective scaffold for the rational design of drug-likes candidates.

Abstract: In this work, the synthesis of 6,6'-([2,2'-bi(1,3,4-oxadiazole)]-5,5'-diyl)bis(3-chloroaniline) (6a) and 5,5'-([2,2'-bi(1,3,4-oxadiazole)]-5,5'-diyl)bis(benzene-1,3-diamine) (6b) was carried out and characterized by spectral data from 1H NMR, ¹³C NMR, IR and mass spectrometry. The optical properties of these compounds were studied, in particular the evolution of reflectance, absorption and band gap energy, and a scanning electron microscopy (SEM) analysis was performed. A comparative in-silico study combining DFT-based reactivity analysis, ADMET prediction, and molecular docking were employed for compounds 6a and 6b. Both exhibited distinct reactivity profiles and strong binding affinities toward DNA Gyrase B (7C7N) and the DNA-ruthenium complex (4E7Y), highlighting their potential as antibacterial agents, as well their potential use in photovoltaic application and for near infrared light shielding basing on the optical results.

Supplementary data PDF (4600 K)

Abstract: Our study aims to develop and validate a newly precise analysis method for simultaneous determination of metalaxyl-M and azoxystrobin residues in wastewater samples. The analysis was done by a series-200 HPLC equipped with a UV detector and C18 column used for separation. Chromatographic separation utilized a mobile phase of 60% acetonitrile and 40% water by volume flowing at a constant rate of 1.2 mL/min and the quantification was performed by measuring absorbance at 275 nm. The proposed method was systematically validated in terms of linearity, accuracy, precision, recovery, limit of detection (LOD), and limit of quantification (LOQ) in compliance with SANCO/3030/99 rev.5 requirements. Calibration curves exhibited excellent linearity (R² > 0.990) across the tested concentration ranges. The obtained LOD and LOQ values indicated high method sensitivity, enabling the reliable quantification of trace levels in complex wastewater matrices. Recovery tests performed at three spiking levels demonstrated satisfactory recoveries ranging from 100.2% to 101.3% for metalaxyl-M and from 99.7% to 101.2% for azoxystrobin, confirming the robustness and reliability of the developed procedure. Overall, the validated HPLC method serves as a versatile, rapid, and economical analytical tool applicable to different environmental and agricultural samples for the monitoring of fungicide residues.

Abstract: This study presents the synthesis and characterization of the novel compound 6,6'-(1,3,4-oxadiazole-2,5-diyl)bis(3-chloroaniline), using 1H NMR, 13C NMR, mass spectrometry and FTIR-ATR infrared spectroscopy. Density Functional Theory (DFT) calculations at the B3LYP/6-311G (d,p) level, were employed to optimize the molecular geometry and evaluate electronic properties. Frontier molecular orbital, molecular electrostatic potential, Parr function, and electron localization function analyses revealed an ambiphilic character, with electrophilic sites localized on the oxadiazole core and nucleophilic regions on the chloroaniline moieties. Molecular docking demonstrated high binding affinities toward Topoisomerase IV, Tubulin, and CDK2, surpassing standard ligands and indicating potential antibacterial and anticancer activities. ADME/Toxicity predictions suggested good pharmacokinetic behavior and low toxicity. Monte Carlo and molecular dynamics simulations confirmed strong and stable adsorption of the novel compound OBA on the Fe (110) surface, supporting its efficiency as a corrosion inhibitor.

Abstract: Acetamiprid, a widely utilized neonicotinoid insecticide, plays a crucial role in modern pest management. However, its widespread use raises questions about possible environmental hazards, including as effects on ecological balance, soil and water quality, and non-target creatures. This review offers a thorough examination of acetamiprid's environmental destiny, toxicity, and risk assessment techniques. It covers the mechanisms by which it disperses and accumulates, as well as the chemical characteristics that affect its persistence and degradation in different environmental matrices. The assessment also looks at current management techniques, such as best practices, regulatory frameworks, and alternative approaches, that are meant to mitigate negative environmental effects. This work highlights the necessity of integrated risk assessment and management to enable effective pest suppression while protecting environmental health, underscoring the significance of sustainable pest control.

Abstract: The removal of synthetic dyes from wastewater is an urgent environmental issue due to their toxicity and persistence. This study explores the use of White Bean Straw, an abundant agricultural residue, as a low-cost and eco-friendly adsorbent for removing Malachite Green and Methyl Red in a fixed-bed system. Adsorption experiments examined the effects of bed height, flow rate, and dye concentration. Optimal performance occurred at a 5 mL/min flow rate, 10 mg/L dye concentration, and 2 cm bed height, achieving adsorption capacities of 28.96 mg/g for Malachite Green and 27.27 mg/g for Methyl Red dyes. Higher bed height and dye concentration enhanced efficiency, while lower flow rates improved performance. Breakthrough data fitted well with the Adams–Bohart, Thomas, and Yoon–Nelson models (R² ranged from 0.921 to 0.986). Overall, White Bean Straw proved to be an effective, sustainable, and low-cost adsorbent for dye-contaminated wastewater treatment.

Abstract: Some new 2-(2H-chromen-3-yl)-[1,3,4]oxadiazole derivatives 8a-e using Huisgen synthesis of 1,3,4-oxadiazoles reaction. Their structures were verified by 1H NMR and and elemental analyses. Compounds 8a-e were tested against 60 human cancer cell lines for in vitro cytotoxic activities according to the international scientific programme of the US National Institute of Health – DTP (Developmental Therapeutics Program), National Cancer Institute (Bethesda, Maryland, USA). Compounds with moderate activity against certain cancer cell lines were identified. In addition, in collaboration with CO-ADD (The Community for Open Antimicrobial Drug Discovery), we have studied the antibacterial activity against the ESCAPE group of strains and the antifungal activity against C. Albicans ATCC 90028 and C. Neoformans ATCC 208821. The studies allowed us to identify 3-[5-(6-bromo-2H-chromen-3-yl)-[1,3,4]oxadiazol-2-yl]-pyridine as a compound with high antibacterial activity against E. Coli ATCC 25922 with MIC 8 μg/ml. Docking studies have shown high affinity of this compound for the bacterial DNA gyrase of Escherichia coli.

Abstract: Dye-sensitized solar cells (DSSCs) represent a highly promising new generation of photovoltaic devices that offer an attractive alternative to traditional silicon-based solar cells due to their low production costs, simple manufacturing, and adaptable optoelectronic properties. Titanium dioxide (TiO₂) is extensively utilized as a semiconductor in DSSCs due to the favorable position of its conduction band, high chemical stability, abundance, and non-toxicity. As part of this work, an in-depth computational study was conducted on five organic dyes (D1 to D5) to investigate their potential as effective sensitizers for DSSC applications. Density functional theory (DFT) and time-dependent DFT (TD-DFT) were employed to investigate their structural, electronic, and optical properties, as well as their key photovoltaic parameters. The HOMO energy levels calculated (−5.99 to −6.36 eV) were low enough to allow efficient dye regeneration by the electrolyte, while the LUMO levels (−3.05 to −3.71 eV) were located above the conduction band edge of TiO₂ (−4.0 eV), Calculated band gaps (2.35–2.94 eV) supported strong absorption in the visible range, and open-circuit voltages (0.26–0.94 eV) suggested good photovoltaic potential. Furthermore, all dyes presented positive free electron injection energy (ΔGinject), evidencing thermodynamically favorable charge transfer processes. Benchmarking revealed that structural modifications between dyes were found to be significantly.

Abstract: The reactions between 2,3-dimethylbutadiene and six azodicarbonyl derivatives give the aromatic α-amino ketone family which presents a great interest in chemical synthesis and especially in polymerization reactions. This reaction was studied using the Molecular Electron Density Theory. The reaction pathways were established using the Intrinsic Reaction Coordinate (IRC) method and confirmed through topological analysis of the Electron Localization Function (ELF). The substituent effect was discussed from the CDFT and GEDT calculations. The temporary formation of hydrogen bonds at TSs is responsible for the mechanistic aspect and the process asynchronous of new bond formation. Consequently, the reaction proceeds via a non-concerted in two-stages mechanism. Finally, we investigated the potential inhibitory effects of six products against HIV-1-Mpro through molecular docking calculations. Then, their medicinal potential and physicochemical properties were scrutinized, employing the SwissADME server, unveiling their non-toxic characteristics and positioning them as promising contenders for drug development.

Supplementary data PDF (4600 K)

Abstract: This study presents the synthesis and characterization of the compound 5,5'-(methylenebis(1,3,4-oxadiazole-5,2-diyl))bis(benzene-1,3-diamine), by ¹H NMR, ¹³C NMR and FTIR-ATR infrared spectroscopy and mass spectrometry. A theoretical study was carried out by a comprehensive and hierarchical methodology in order to evaluate the inhibitory behavior of the molecule 5,5'-(methylenebis(1,3,4-oxadiazole-5,2-diyl))bis(benzene-1,3-diamine) with respect to the corrosion of a Fe(110) type metal surface. Thus, examination of non-covalent interactions by NCI analysis. In addition, the study of adsorption on the metal surface was carried out by the Monte Carlo method.

Supplementary data PDF (4600 K)

Abstract: This study explores the mechanism and solvent effects of the (3+2) cycloaddition between N-(4-(prop-2-yn-1-yloxy)phenyl)-1-(pyridin-2-yl)methanimine and 4-azido-7-chloroquinoline, yielding quinoline–triazole hybrids. DFT/B3LYP/6-311G+(d,p) calculations, supported by ELF and NPA analyses, reveal a one-step mechanism favoring product P1 both kinetically and thermodynamically. Non-covalent interaction (NCI) analysis indicates that TS1 is stabilized by hydrogen-bonding and van der Waals interactions. ADMET screening showed that all cycloadducts are non-toxic (no AMES mutagenicity or skin sensitization). Molecular docking identified P3 and P4 as the most potent ligands for Plasmodium falciparum kinases 5E16 and 5DYK, respectively, with stronger binding affinities than chloroquine. Molecular dynamics simulations further confirmed the structural stability of the P3–5E16 and P4–5DYK complexes, highlighting these derivatives as promising candidates for antimalarial drug development.

Abstract: Herein, we theoretically design four new π-conjugated thieno[3,4-b]pyrazine derivatives for organic solar cells (OSCs), denoted 2,3-di([2,2′:5′,2″:5″,2‴-quaterthiophen]-5-yl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine, 2,3-bis(5'''-(4-fluorophenyl)-[2,2':5',2'':5'',2'''-quaterthiophen]-5-yl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine, 2,3-bis(5'''-(4-methoxyphenyl)-[2,2':5',2'':5'',2'''-quaterthiophen]-5-yl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine, and 2,3-bis(5'''-(9-methyl-9H-carbazol-2-yl)-[2,2':5',2'':5'',2'''-quaterthiophen]-5-yl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine. The geometric, electronic, optical, photovoltaic, and nonlinear optical (NLO) properties of the investigated chemical structure were investigated using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) calculations at the B3LYP/6-31G(d,p) level. Structural changes on the chemical structure induce a narrow energy gap in the range (2.08 – 2.12 eV), and an enhancement of the absorption in the visible range (λ_max = 682 – 688 nm). In addition, a low value of exciton binding energies is obtained (E_b = 0.28 – 0.31 eV). Analysis of the density of states (DOS), transition density matrix (TDM), electron localization function (ELF), and localized orbital locator (LOL) showed effective charge delocalization and donor-to-acceptor electron transfer. The photovoltaic performance was assessed using the open circuit voltage (V_oc) obtained between Highest Occupied Molecular Orbital (HOMO) donor to Lowest Unoccupied Molecular Orbital (LUMO) acceptor levels and was found promising (V_oc = 1.32 – 1.44 V). The large hyperpolarizability and high nonlinearity response of the NLO results also indicated the potential for these molecules to be used in various optoelectronic applications.

Abstract: A series of novel conjugates of nalidixic acid with a marine natural product was designed and synthesized. Their antibacterial and antibiofilm activities were evaluated in vitro against Gram-positive (S. aureus ) and Gram-negative (E. coli and P. aeruginosa) bacteria. Most of the compounds exhibited strong antibacterial activity against S. aureus, E. coli, and P. aeruginosa strains, except for the oxacillin-resistant P. aeruginosa. Among them, compound 2, containing a decyl ammonium fragment, showed the highest antibacterial activity, with MIC values ranging from 2 to 8 μg/mL, superior to those of nalidixic acid. In addition, compound 2 inhibited biofilm formation by standard strains of S. aureus, E. coli, and P. aeruginosa, and by colistin-resistant E. coli by 98-100% at a concentration of 4 μg/mL.

Abstract: This work presents a density functional theory study of Ofloxacin (OFL) as a medicine with antibiotic activity. The Conformational behaviour, gas-phase acidity and metal ion affinity (MIA) analysis of the Ofloxacin with some selected cations from alkali (Li⁺, Na⁺, and K⁺), alkaline-earth (Be²⁺, Ca²⁺ and Mg²⁺) and transition (Zn²⁺, Cu²⁺, Ni²⁺, Co²⁺ and Fe²⁺) metals were explored. All structural optimizations were performed at the M06–2X level of theory with 6-311++G(d,p) using the basis set. The calculations demonstrated the following MIA order: OFL-Be²⁺ > OFL-Ni²⁺ > OFL-Co²⁺ > OFL-Cu²⁺ > OFL-Fe²⁺ > OFL-Zn²⁺ > OFL-Mg²⁺ > OFL-Ca²⁺ > OFL-Li⁺ > OFL-Na⁺ > OFL-K+. The results also showed that the MIA values are decrease in aqueous solution because of solvation effects. Natural bond orbital theory (NBO) and quantum theory of atoms in molecules (QTAIM) were used to probe the charge transfer process and the nature of interactions in the formed complexes. The results of the NBO analysis revealed that the charge transfer occurs from OFL and Mn+ with the metal cations acting as charge acceptors and the amount of charge transfer is in agreement with MIA. The QTAIM analysis shows that the (M–O) coordination interactions are quasi-covalent in complexes formed between OFL and alkali or alkaline-earth metal cations, whereas they are covalent in complexes formed with the transition metal cations and Be²⁺. The results confirm that the strengths of the interactions are in good agreement with electron densities at the bond critical points (BCP).

Supplementary data PDF (4600 K)

Abstract: A convenient method has been developed for the synthesis of a focused library of eight 3-arylimidazo[2,1-b][1,3]thiazoles 4a–h, seven of which have been obtained for the first time. The approach is based on the cyclization of 2-(aroylmethylthio)imidazoles 3a–h under the action of polyphosphoric acid. The structure of the intermediate derivatives of thioimidazoles 3a-h and the imidazothiazoles 4a-h thus obtained was characterized using ¹H, ¹³C NMR spectra and LC-MS. Testing all obtained compounds for antioxidant activity showed that 2-[(1H-imidazol-2-yl)thio]-1-arylethanones 3a–h exhibit a higher ability to inhibit DPPH radicals compared to their cyclic analogues, 3-arylimidazo[2,1-b]thiazoles 4a–h. The highest antioxidant activity was demonstrated by compound 3b (I = 96.3%), which also showed high binding affinity to the Kelch domain of the Keap1 protein in docking studies.

DOI: 10.5267/j.ccl.2025.12.002
Keywords: Imidazo[2,1-b][1,3]thiazone, Polyphosphoric acid, Еlectrophilic intramolecular cyclization, Antioxidant activity

Supplementary data PDF (4600 K)