Advanced Journal of Chemistry, Section A
Volume:7 Issue: 4, Autumn 2024

This work uses the density functional theory (DFT) method to investigate the adsorption of transition metal cations (Cr2+, Mn2+, Fe2+, Cu+, Ag+, and Au+) on a single-walled boron nitride nanotube (SWBNNT). The systems with the highest adsorption energy within each ion group are the Fe2+@BNNT and Au+@BNNT, with observed values of -1474.30 and -242.15 kJ.mol-1, respectively. However, the Mn2+@BNNT and Ag+@BNNT structures exhibit the lowest values, measuring at -816.51 and -173.25 kJ.mol-1, respectively. The density of states computation is illustrated to validate the outcomes attained. The results from our analysis of electronic characteristics indicate that the percentage change in energy gap (%ΔE) is higher in the divalent complexes compared to the monovalent structures. The Fe2+@BNNT complex exhibits the smallest HOMO–LUMO energy gap, measuring 5.760 eV. This is followed by Cr2+@BNNT and Mn2+@BNNT, with energy gaps of 5.659 eV and 5.755 eV, respectively. However, the corresponding values for Au+@BNNT, Cu+@BNNT, and Ag+@BNNT are 6.046, 6.821, and 6.471 eV, respectively. Therefore, the divalent ions have the potential to be excellent candidates for enhanced adsorption capability.

Pristine TiO2 nanoparticles, doped with single elements Cu and Mg, were synthesized utilizing the sol-gel process with titanium tetraisopropoxide as the Ti basis. The physicochemical characterizations of the nanoparticles were evaluated using X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflection spectroscopy (DRS), and scanning electron microscopy (SEM). The XRD shapes of the samples did not display isolated peaks of diffraction for Cu or Mg, demonstrating that the metals were well spread on the TiO2 surface. The DRS analysis uncovered an intriguing finding- the co-doped photocatalyst exhibited a significantly narrower band in comparison to both un-doped and monometallic TiO2. This intriguing alteration in the absorption band near visible light holds great potential. To further explore its implications, a comprehensive comparison was conducted to evaluate the photocatalytic activity of nanoparticles in degrading orange G solution under visible light. TiO2 nanoparticles doped with copper and magnesium exhibited significantly higher photocatalytic activity than to Cu/TiO2, Mg/TiO2, and pure TiO2 nanoparticles. The optimal doping levels of copper and magnesium for the synthesis of Cu and Mg/TiO2 nanoparticles were determined to be 1 and 0.25 mol%, respectively.

This study aimed to investigate alterations in the physical and chemical properties resulting from hydrothermal carbonization process applied to dried coconut pulp samples. The samples were passed through a 50-mesh sieve, immersed in demineralized water, and subjected to heating in an autoclave soaked in silicone oil at 200 °C for 5 hours. Hydrochar product (HTC-coconut pulp) of the treatment is a black powder characterized using several instruments. The results of X-ray diffraction (XRD) analysis showed that the peaks in coconut pulp occurred at 2θ: 16.1°, 20.3°, and in the corresponding HTC-coconut pulp at 2θ: 20.2°, 21.2°. Meanwhile, analysis using FTIR showed a significant change where the peaks were at wavenumber (cm-1) 3603, 2926, 2855, 1746, 1462, 1372, and 1155. The peaks detected in HTC-coconut pulp were at wavenumber (cm-1) 2929, 2849, 1713, 1468, 1290, 1117, and 1057. The results of X-ray fluorescence (XRF) analysis showed several elements such as Al, P, S, Cl, K, and Ca, while HTC-coconut pulp showed Al, Si, P, S, Cl, K, and Ca. A simple application of the two types of materials was as an adsorbent for a simulated methylene blue (MB) solution. According to UV-Vis spectrophotometry absorbance before and after treatment, HTC-coconut pulp showed a slightly higher absorbency compared to normal coconut pulp.

In recent years, there has been an increase in the consumption of pharmaceuticals, especially antibiotics. Tetracycline (TC) is one of the widely used antibiotics, as it causes resistance to all microorganisms in ecosystems. In addition, it is classified as a controlled antibiotic. In this work, the efficiency of TC drug degradation via photolysis and hetero-generous photo catalytic methods is studied under effect of several volumes of H2O2 (0-4 mL) as an oxidizing agent. Characterization of the sample was carried out via UV-visible spectroscopy, XRD, FESEM, EDX, and TEM. The reveal results the photocatalytic degradation of TC drug is 92.67 %, at the best conditions weight of catalyst ZnO NPs 0.3 g, volume of hydrogen peroxide (3 mL), and concentration of TC drug 50 mg/L, pH=6, at irradiation time 60 min. H2O2 doses (0 and 4 mL) appear to have important variances in the first 10 min of the reaction for 4 mL of H202 comparative with the solution without H2O2 giving the best PDE% (98.44%). The (PDE%) rises as concentration of TC drugs decreases from (92.67%-29.76%), but light intensity increases. Regeneration/recycling of ZnO NPs the photo catalytic degradation efficiency was 88.9 %, 82.8 %, and 77.5% through 4 cycles compared to standard solution(fresh) was 92.67 %.

In this article, a heterogeneous and recyclable Lewis acid, zirconium chloride immobilized on Arabic Gum (ZrCl4@Arabic Gum) was used for the synthesis of Dihydropyran derivatives. Accordingly, Dihydropyran derivatives were synthesized with multicomponent reactions, without solvent, using different aldehydes in the presence of the mentioned catalyst at 50 °C. nano- ZrCl4@Arabic Gum was used as a recyclable catalyst in organic synthesis. The advantages of this method compared to the previous works are high reaction efficiency, short time, simple operation, and catalyst recycling without significantly reducing the catalytic ability.

A succinct total synthesis of an indoloquinoline alkaloid was achieved through a one-pot, two-step process involving a cascade of sodium hydride and aniline, followed by a base-mediated Claisen condensation reaction. Subsequently, the reaction was conducted via microwave-assisted synthesis (MAS), resulting in a good yield of the title compound with eco-friendly methodologies. The structural properties of the synthesized compound were validated using FT-IR, 1H-NMR, 13C-NMR, and GC-Mass spectral analyses. In addition, FT-IR approaches were employed to compare the vibrational wavenumbers obtained through simulation with experimental wave numbers. Furthermore, DFT calculations were employed to fine-tune the structural parameters and investigate FMOs, Mulliken atomic charges, MEP, and NLO properties, and molecular docking studies evaluated its N3 binding site of the primary coronavirus protein 6LU7. Likewise, the title compound is assessed for its ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) properties, revealing promising pharmacokinetic profiles devoid of any detected indications of non-toxicity.

The hydrothermal synthesis of ZnO/CdS nanocomposite studied for photocatalytic degradation of Amoxicillin (AMX) drug. The physical and chemical properties of the prepared ZnO/CdS were characterized using several analyses such as TEM, FE-SEM, TGA, and EDX. The photodegradation of Amoxicillin (AMX) drug was studied by employing UV-Vis light under several conditions in the presence of ZnO-CdS nanocomposite. Influence of several parameters such as AMX concentration (10-80 mg/L), mass of nanocomposite (0.1-0.4 g), and regeneration of ZnO-CdS nanocomposite was studied and optimized. All experiments were carried out under the most optimum conditions, which included a drug concentration of 30 mg/L, a light intensity of 1.2 mW/cm2, and a solution pH of 6.8. The results showed that the photocatalytic efficiency rose with reducing concentration of AMX (95.99%-53.12%) when concentration increased from 10 to 80 mg/L. The photocatalytic degradation increased when the weight of the ZnO-CdS nanocomposite increased (44.43%-98.99%). It was observed that the photocatalytic efficiency of AMX was 80.86%-72.77.85% for the first to fourth cycles. This indicates the best stability of nanocomposites and could be potentially useful in practical batch degradation.

Glycols and diols, compounds characterized by the presence of two hydroxyl (-OH) groups, play a pivotal role in numerous chemical and industrial processes owing to their distinctive properties, including water solubility, pharmaceutical applications, antifreeze capabilities, and solvent properties. The principal function of a protecting group lies in temporarily concealing a reactive functional group within a molecule, thereby averting undesirable reactions while allowing other reactions to proceed unhindered. Dimethoxytrityl (DMT) stands out as a commonly employed protecting group in organic synthesis, notably in the realms of oligonucleotide and peptide synthesis. Selective DMT protection of the compounds included in the study were achieved through manipulation of temperature and limiting reagent concentration using cannula transfer in the experiments contributing to the study. The primary hindrance of traditional methodologies for synthesis of mono-DMT-protected compounds lies in the incorporation of high-cost purification of the desired products. This article outlines a chromatography-free methodology for synthesizing mono-DMT-protected derivatives of glycols and diols resulting in high yields and   purity employing economically efficient purification methods such as extraction and precipitation. Characterization is achieved through thin-layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS). Additionally, conducted by undergraduate researchers, this methodology boasts affordability, swiftness, and operational simplicity. Given these merits, it stands as a viable option for inclusion in organic chemistry I and II laboratory projects.

A newer generation pyrimidine derivatives were designed, synthesized, and evaluated in vitro alpha amylase and bacterial growth inhibitor. The molecules' design fully depended upon the structural features of previously pyrimidine derivatives. Then all the designed molecules (SD1-SD100) were docked with 1OSE pig pancreatic alpha-amylase isoenzyme. S-[4-(2-hydroxyphenyl)-6-phenylpyrimidin-2-yl] benzenecarbothioate, S-(4,6-diphenylpyrimidin-2-yl) benzenecarbothioate, S-[4-(4-hydroxy-3-methoxyphenyl)-6-phenylpyrimidin-2-yl] benzenecarbothioate, and S-[4,6-bis(4-hydroxyphenyl)pyrimidin-2-yl] benzenecarbothioate showed good docking interaction scores, as compared to acarbose. The interacting residues of the synthesized molecules and 1OSE showed similar amino acid lining as present in the active site. The synthetic procedure of the molecules was divided into two steps such as synthesis of chalcone derivative using aromatic aldehyde and acetophenone, reaction between chalcone and thiourea to form substituted pyrimidine-2-thiol, then finally substituted pyrimidine-2-thiol and benzoyl chloride reacted in presence of glacial acetic acid to obtain the best docked molecules. All the molecules show characteristic peaks in FTIR, 1H-NMR and Mass spectrometric data. Among all the synthesized molecules S-[4-(2-hydroxyphenyl)-6-phenylpyrimidin-2-yl] benzenecarbothioate showed best in vitro alpha amylase inhibition activity. Also, all synthesized molecules showed moderate to good antibacterial activities.

Coronavirus, which is one of the viruses that caused severe effects, started in 2019; many deaths all over the world have been recorded. It is a virus that causes cough, shortness of breath, hyperthermia, and acute respiratory syndrome, followed by shortness of breath and death. Despite the creation of several vaccines that enable us to control the Coronavirus, we still do not have an effective medicine to treat it; our aim is to find out using molecular docking a drug with good activity against COVID-19. In this study, we used the GOLD program, which is one of the simulation programs, and we examined several compounds for their extent of association with the enzymes of the protease, baby-like protease, etc. The result is that roxithromycin may be highly effective for treating the coronavirus and contains high binding rates, and the compound TT, where the binding rate reached 97%. In this study, we have estimated the binding affinity for Papain-like protease and RNA-dependent RNA polymerases of SARS-CoV-2 as the control molecule, and our result was that roxithromycin had the highest binding affinity. Our study concluded that after conducting molecular docking against 3 enzymes, Mpro, PLpro, and RdRp, Roxithromycin showed promising docking results. Combating the novel coronavirus with roxithromycin alone or with other medication could be possible.