Chemical Review and Letters

Abstract In the current study, density functional theory (DFT/ωB97XD) is used to investigate the cation–π interactions in complexes of Altretamine-M (M = Fe2+, Zn2+, Si2+, Ge2+, Mg2+, and Ca2+) in the gas phase and solution. Overall, metals contribute to drug interactions through coordination chemistry, redox activity, enzyme modulation, metabolic transformations, and impacts on pharmacokinetics and pharmacodynamics. Metals as drug components or through metal ion interactions can also affect drug solubility, stability, and delivery, influencing absorption and bioavailability. The results display that the binding strength in the gas phase is higher than in the solution phase. The chemical bonding properties and population analysis of the structures are evaluated using the atoms in molecules (AIM) and natural bond orbital (NBO) analyses. According to the obtained results, all the cation-π interactions in the studied complexes have a closed-shell nature. The aromaticity of the complexes is assessed using two widely recognised indices, which facilitate detailed evaluation of the electronic structure and aromatic character of the molecules. The NMR analysis is performed to calculate some coupling constants and nitrogen shielding tensors in the complexes. Finally, the electronic properties of structures are estimated using different conceptual DFT parameters.

Abstract Oxidative stress (OS) is a primary contributor to sperm DNA fragmentation (SDF) and impaired male reproductive function. Numerous studies have demonstrated the advantages of natural antioxidants; however, evidence supporting the efficacy of synthetic antioxidants is limited and inconclusive. This study aimed to assess the effectiveness of laboratory-synthesized synthetic compounds in the preservation of sperm DNA. This study aimed to evaluate the effectiveness of laboratory-synthesized synthetic compounds in maintaining the integrity of sperm DNA. The study a Schiff's base ligand [L] from L-asparagine and 4-dimethylaminobenzaldehyde, as well as its heavy metal complexes, utilizing FT-IR, UV–Vis, 1H/13C-NMR, conductivity tests, and magnetic susceptibility analysis. We used the DPPH method to test how well the synthesized compounds worked as antioxidants. The Comet test was used to see how well the chemical protected sperm DNA. Hydrogen peroxide made sperm DNA fragmentation a lot worse. Treatment with the free Schiff base ligand [L] reduced damage in a dose-dependent way, with the 50 µg/mL dose bringing head DNA (HD%) back to roughly 92% (P < 0.001), which is the same as ascorbic acid. Metal complexation greatly increased protection. [Mn₂(L).3Cl.H₂O] and [Co₂(L).3Cl.H₂O] kept more than 99.9% of head DNA (HD%) and reduced tail DNA (TD%) to less than 0.12% (P < 0.0001 compared to the H₂O₂ group). The Zn(II) compound only protected about 80% of the head DNA (HD%). The DPPH IC₅₀ values were in line with functional protection, which showed that Mn and Co complexes worked as antioxidants. Schiff-base metal complexes, specifically Mn(II) and Co(II), exhibit notable antioxidant capabilities that protect sperm DNA and may be utilized in in vitro sperm washing media. However, additional preclinical investigations are required to confirm their safety and efficacy.

Abstract This research employed density functional theory (DFT) calculations to assess the potential of both unmodified and lithium-enhanced Triazasumanene (TAS) nanostructures as sensors for detecting the hazardous hydrogen cyanide (HCN) gas. The findings from adsorption energy and thermodynamic parameter analysis indicated that pristine TAS interacts weakly with HCN, showing minimal changes in its bandgap (Eg). To improve its sensing capability, TAS was altered by incorporating a lithium atom, resulting in Li@TAS. The calculated negative adsorption energies and thermodynamic data suggested that HCN adsorption on Li@TAS is thermodynamically favorable, exothermic, and spontaneous under experimental conditions. The density of states analysis revealed a notable 8.38% reduction in the bandgap of Li@TAS, decreasing from 1.49 eV to 1.36 eV. Further exploration of interaction characteristics through NCI and RDG analyses demonstrated a strong bond between the nitrogen atom of HCN and the lithium atom on the modified TAS. Additionally, NBO charge analysis confirmed significant charge transfer between HCN and Li@TAS in both tested configurations, measuring 36 me and 28 me, respectively. Overall, the study concludes that lithium-decorated TAS is a promising candidate for effectively detecting HCN gas.

Abstract Polymers and heterocyclic compounds according to their chemical character play important roles in many biological systems according to their functions as excipients and inert carriers of other pharmacological active compounds. This research we synthesis some of their compounds via Bis (4-aminophenyl) methane. the first step react this compound with some substituted of benzaldehyde to form Schiff base (G1-G3) and cyclization of these Schiff base by sodium azid to form substituted of tetrazole (G4-G6) and polymerized this Schiff base by hydrazine hydrate to form ( G7-G9) compounds and the other step Bis (4-aminophenyl) methane react with ammonium thiocyanate and glacial acidic acid and cyclized it to bis 2-amino benzo thiazole methane (G10) and reacted it with to terephthaloyl dichloride form polymer benzo bis thiazole methane amide derivative (G12),and studying Thermogravimetric analysis (TGA) revealed varying thermal stability among the synthesized polymers. Polymer G12 exhibited the highest thermal stability with 83% residue at 300 °C, attributed to its high aromatic content. In contrast, polymers G22 and G23 showed lower stability with residue values ranging from 0–42%, likely due to decreased aromatic and increased aliphatic content. Polymer G24 demonstrated moderate stability (up to 52%), highlighting the positive influence of aromatic structures on polymer thermal resistance.

Abstract This study delves into the potential of six different natural cyclodextrins, including alpha-cyclodextrin, beta-cyclodextrin, and gamma-cyclodextrin, and modified CDs like Amino-BCD, methylated-BCD, and 2-hydroxypropyl-beta-cyclodextrin, in Sunitinib, a potent inhibitor of multiple tyrosine kinase receptors with significant antitumor effects. Computational techniques such as molecular docking and molecular dynamics simulation were employed in this exploration. The molecular docking results reveal that Sunitinib forms inclusion complexes with all six CDs, with the highest affinity observed with methylated-beta-cyclodextrin. RMSD analysis of MD simulation trajectories confirm the formation of stable complexes of Sunitinib with all six CDs. However, according to the distance analysis, it can be inferred that among all the natural and modified CDs, gamma-cyclodextrin and methylated-beta-cyclodextrin have the most dependable interaction complexes with Sunitinib. The reduced hydrogen bond formation with the solvent in inclusion complexes compared to free CDs indicates that Sunitinib displaces water molecules from the internal wall, highlighting the formation of hydrogen bonds between the CDs and Sunitinib and underscoring the potential of CDs for drug encapsulation. Interaction energy analysis emphasizes the significant role of van der Waals interactions in the encapsulation of Sunitinib within CDs and suggests that methylated-beta-cyclodextrin and beta-cyclodextrin are the optimal choices for the delivery of Sunitinib.

Abstract This review, which covers the literature from 2020 to 2025, aims to provide a thorough insight into the synthesis of β-mono-/di-/-tri-fluoromethylated carbonyl compounds via direct vicinal acyl-mono/-di/-tri-fluoromethylation of alkenes also highlighting their mechanistic accepts that may provide new insights into catalyst improvement and development.

Abstract This study presents the synthesis and characterization of Azo, Schiff base, and novel β-lactam derivatives. The Azo derivative (A1) was synthesized by coupling the diazonium salt prepared by dissolving 2-(aminomethyl)aniline in acidic medium at (0-5)°C with 4,5-diphenyl-1H-imidazole. The Schiff base derivative (S1) was then synthesized by reacting the Azo derivative prepared in the previous step with 3-phenyl-1H-pyrazole-4-carbaldehyde. Finally, the β-lactam derivative (B1) was prepared by reacting the Schiff base derivative prepared in the second step with triethylamine and Chloroacetyl chloride. The structural characterization of the synthesized compounds was carried out using (FT-IR), (1H-NMR) and (13C-NMR) spectroscopy. The molecular docking of the beta-lactam derivative against the breast cancer-associated MCF-7 protein was studied, revealed a binding affinity of (−8.78kcal/mol), indicating a strong interaction between the ligand and the target protein. Furthermore, the root-mean-square deviation (RMSD) value of (2.40Å) suggests a stable and consistent binding conformation within the active site indicating strong potential as an anticancer agent. Biological assays demonstrated selective toxic activity against MCF-7 breast cancer cells with an IC₅₀ of (102.2μg/mL), while showing less toxicity to normal WRL-68 cells (IC₅₀ = 230.1μg/mL).

Abstract Today, in a period of global climate change and environmental problems, the world is experiencing a decline in the productivity of agricultural crops. The need for effective chemical compounds that control the growth of cultivated plants and increase their productivity is increasing. In world agriculture, obtaining stimulants that are low in toxicity and highly effective, increasing plant productivity and combating various harmful insects and phytopathogenic microorganisms are important issues. It is known that 4-chlorophenoxyacetic (4-D) and 2,4-dichlorophenoxyacetic (2,4-D) acids are widely used in agriculture as herbicides and plant growth stimulants. 2,4-D, which is considered a systemic herbicide, moves easily in the plant body together with nutrients and metabolic products and leads to general poisoning (deformation of plant stems and leaves, their brittleness, growth retardation). This is an important factor in controlling perennial weeds with a well-developed root system. Contact and systemic herbicides are sprayed on the surface of the plant leaf, as well as introduced into the soil. 2,4-D has a selective effect mainly on dicotyledonous weeds, so it is widely used in monocotyledonous crop fields. On the basis of these compounds, many studies have been conducted on the synthesis of highly biologically active complex compounds and the study of their molecular and crystal structures and the determination of their mechanism of action. As a rule, these compounds exhibit herbicidal properties in high concentrations, but in microconcentrations (less than 0.001%) they serve as plant growth accelerators (stimulants).

Abstract This research presents the first theoretical investigation of 5-methyl-2-oxo-1,3-oxazolidine-4-carboxylic acid (MOCA) using Density Functional Theory (DFT) at the B3LYP/6-311G(d,p) level. The primary objective is to explore MOCA’s structural, electronic, and nonlinear optical (NLO) properties, with emphasis on its response to UV illumination. Geometry optimization reveals a stable molecular framework, while Frontier Molecular Orbital (FMO) analysis demonstrates a significant reduction in the HOMO-LUMO energy gap upon UV exposure—from 4.66 eV in the ground state to 2.09–2.22 eV in the excited triplet state—indicating enhanced charge transport characteristics suitable for use as a window layer in photovoltaic devices. Furthermore, computed polarizability and first-order hyperpolarizability (βtot) values show strong NLO activity; βtot decreases from 4.41 × 10⁻³⁰ esu before UV to 3.66 × 10⁻³⁰ esu after irradiation, yet remains substantially higher than urea (0.3728 × 10⁻³⁰ esu), highlighting MOCA’s potential for applications in frequency doubling, optical switching, and electro-optic modulation. The observed photoresponsiveness suggests avenues for developing smart, tunable photonic materials. This work provides foundational computational data for MOCA, filling a critical gap in the literature and paving the way for future experimental validation.

Abstract Recent studies have identified B₄₀ fullerenes as promising candidates for biosensing applications, including the detection of medicinal agents, drug delivery, and gas nanosensing. In the present study, the adsorption behavior of carmustine on pristine B₄₀ and metal-encapsulated fullerenes (Mg@B₄₀ and K@B₄₀) were investigated to evaluate their sensing capabilities using Density Functional Theory (DFT) calculations. The results revealed that the adsorption energies of carmustine on M@B₄₀ (M = Mg, K) were higher than pristine B₄₀ fullerene, with thee most stable conformer exhibiting an adsorption energy of –16.54 kJ/mol. Furthermore, the energy gap, defined as the difference between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), decreased upon carmustine adsorption, indicating an enhancement in enhanced electrical conductivity. Further more, Analysis of dipole moments and recovery times of the resulting complexes confirmed that these systems possess potential as Φ-type sensors for the selective detection of carmustine.

Abstract This study investigates the novel synthesis of Mannich base complexes, including V(IV), Ru(III), Pt(IV), and Au(III), which are produced from the Acyclovir-Mannich base. All structures of these novel compounds were described using spectroscopic approaches, including 1H,13C-NMR, UV-Vis, mass spectrometry, FTIR, metal, and elemental analysis, in addition to magnetic susceptibility and conductivity measurements. The diagnosis found that the VO-complex possesses a square pyramidal geometry, the Au-complex exhibits square planar geometry, and the Ru and Pt complexes are octahedral. All synthesized compounds were subjected to the antioxidant assay. The antioxidant activity indicates that the Ru (III) complex exhibited superior antioxidant efficacy compared to the others. The value of IC50 concerning this combination was 311.50 μg/ml. The study also involves evaluating the efficacy of these compounds in inhibiting the bacteria Acinetobacter baumannii, a Gram-negative, and Streptococcus pyogenes, a Gram-positive, as well as their antifungal activity against the microorganism Candida albicans, utilizing two separate concentrations (50 and 100) mg/ml. The data indicate that higher concentrations enhance antibacterial and antifungal action, and the Pt-complex exhibits more synergistic effectiveness and demonstrates excellent antibacterial properties against Streptococcus pyogenes.

Abstract Methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI) remain the dominant aromatic diisocyanates used to produce polyurethanes (PUs), a class of polymers with unparalleled versatility spanning foams, elastomers, coatings, adhesives, and specialty materials. This review synthesizes the literature (with emphasis on the last ~7 years) to present: (1) the core chemistry of MDI- and TDI-based polyurethane formation and modern synthetic/processing variants (prepolymers, blocked isocyanates, latent systems); (2) structure–property relationships arising from hard/soft segment microphase separation, crosslink density, and formulation additives; (3) major advances in high-performance formulations including thermoplastic polyurethanes (TPUs), nanocomposites, and dynamic/dissociative networks (vitrimers) that enable reprocessing and self-healing; and (4) sustainability trends - bio-based polyols, non-phosgene and greener isocyanate routes, and chemical recycling strategies. This review highlights key enabling chemistries (transcarbamoylation, urethane exchange, glycolysis-derived feedstocks), summarizes representative performance gains from nanofillers and modified formulations, and discusses technological challenges for scaling sustainable and recyclable PU systems. Finally, recommendations are offered for research directions that are likely to accelerate the adoption of circular, lower-toxicity MDI/TDI-based PUs across major application sectors.

Abstract The article examines the development of a stable lubricant enhanced with colloidal graphite, utilizing recycled 15W40 diesel engine oil thickened with calcium soap. The study reveals that increasing the graphite concentration results in a gradual rise in water content, while the amount of thickener remains unchanged. Furthermore, higher graphite levels lead to a reduction in penetration values, decreasing from 440 units to 310 units. This suggests an improvement in grease consistency and stiffness. The dropping point also shows notable changes, increasing from 79°C to 88°C at a graphite concentration of 150 ppm, before declining to 81°C with further graphite additions. Regarding anti-wear performance, the smallest wear scar diameter is observed at the same 150 ppm concentration, measuring 0.215 mm—25.1% smaller than that of the control sample.