Journal of The Chinese Chemical Society最新文献

Pharmaceutical substances, a pill for every ill, have become a sweet poison by remarkably boosting the global economy as well as human and animal wellness and at the same time causing environmental pollution, especially in the aquatic ecosystem, and this has led to a fatal diminution in the availability of clean water and upsurge in water insecurity. Notably, traditional techniques and materials have been employed to clean up pharmaceutical pollutants (PP) from aquatic bodies; however, they have come under controversy because they require hazardous chemicals and cannot fully mineralize stubborn PPs. Interestingly, the photocatalytic degradation approach employing eco-benign biosynthesized nanoparticles (BNP) is an avant-garde practice and has shown to be an eco-sustainable method that can fully mineralize PPs into harmless molecules. Thus, this study critically explores the application of BNPs for the photocatalytic degradation of PPs. The review revealed that the greatest degradation efficacy of BNPs was greater than 80% in most cases, and that the least amount of time required was around 10 min. In addition, the oxygen-containing functional groups found in the biological sources used for the fabrication of BNPs contributed to the supremacy of ^•OH and O₂^• radicals in the degradation operation. Also, the photocatalytic degradation kinetic data was well modeled by pseudo-first order, and this indicates that ^•OH was more involved in the PPs degradation operation than O₂^•. Moreso, BNPs have excellent reusability potential (>5 rounds) while maintaining inherent structural integrity. Techno-economic analysis revealed that BNPs are cost-effective, costing about $1.5/1,000,000 mL of pharmaceutical wastewater on average.

This figure gives the solvent effect described using two different solvation models (the linear response and state-specific schemes) on the energy, dipole moment, and oscillator strength involved in a vertical excitation of the solution-phase organic molecule. More details about this figure will be discussed by Dr. Shih-I Lu and his co-worker on page 1045-1051 in this issue.

The crystal structure of Michaelis complex of the bovine trypsin with N-α-benzoyl-l-arginine ethyl ester (BAEE) was determined at 2.30 Å resolution. The structure of enzyme-substrate complex was solved in space group H3₂. The active site of trypsin was found to be occupied with the N-α-benzoyl-l-arginine ethyl ester. The hydrolyzed product of substrate molecules was also crystallized with trypsin. The substrate was embedded within the S1 binding site of the enzyme, and showed contacts with Gly-195, Ser-216, and Ser-192. Some water molecules were also found within the vicinity of catalytic residues of enzyme. Interestingly, the hydrolyzed product present within the crystal lattice was found to be with inverted configuration. The crystal structure of trypsin in-complex with N-α-benzoyl-l-arginine ethyl ester has never been reported previously.

The design, synthesis, and characterization of novel BODPY-based iridium and ruthenium complexes were reported. The structures of new compounds were fully characterized by FT-IR, MALDI-TOF mass analysis, elemental analysis, ¹H, and ¹⁹F NMR spectroscopies. Precursor BODIPY was characterized by single-crystal x-ray diffraction technique for the first time. Photophysical properties including absorption and emission profiles and lifetimes were investigated via UV–vis absorption and emission spectroscopy. Photochemical properties were investigated via direct method, and the singlet oxygen production capabilities of new complexes were determined by NIR phosphorescence methods. BODIPY-based new complexes were efficient at producing ¹O₂. Besides, both complexes showed more remarkable photosensitization ability than some commonly used photosensitizer based on BODIPY derivatives. This study points out that novel complexes are effective ¹O₂ photosensitizers that might be used for different application areas like photodynamic therapy.

In this study, we present a detailed analysis of the structural forms of asymmetric curcuminoids through single-crystal X-ray diffraction and nuclear magnetic resonance (NMR) spectroscopy. Curcuminoids substituted with electron-withdrawing groups (Cl and Br) predominantly adopt the β-keto-enol form, whereas those with an OMe group exhibit both diketo and β-keto-enol forms. Variable-temperature X-ray diffraction studies confirm that the structural state of curcuminoids is influenced by temperature. Our findings also reveal that the β-keto-enol form is favored in acidic and neutral conditions, while the diketo form is more prevalent in basic environments. The theoretical Density Functional Theory (DFT) calculations further elucidate the energy differences between the diketo and β-keto-enol forms, emphasizing the significance of electronic effects and temperature on tautomeric distributions. These insights enhance our understanding of the structural dynamics of curcuminoids, with implications for their biological activity and pharmacological applications.

NH₃ is a highly promising zero-carbon fuel. In this paper, 19 important reactions involving NH₃, NH₂, and NH in the ammonia system are studied to better establish the combustion reaction mechanism of ammonia. These reactions encompass the reactions of NH₃, NH₂, and NH with free radicals and inorganic compounds such as O, H, OH, NO, H₂O, and O₂. Utilizing the transition state theory and Yao-Lin method, energy barrier diagrams for these reactions are presented, and the harmonic and anharmonic rate constants are calculated over the temperature range from 300 to 4000 K. The calculation results reveal that, in most reactions, the harmonic rate constants exceed the anharmonic rate constants and the experimental results are closer to the anharmonic rate constants. Additionally, the kinetic and thermodynamic parameters are fitted. To summarize, most reactions are significantly influenced by the anharmonic effect.

Vanillin is often used in food and medicine because of its unique flavor and pharmacological effects. However, excessive vanillin intake can harm human health; therefore, rapid and simple vanillin detection methods are required. In this study, porphyrin-based conjugated microporous polymer-grafted graphene (CMP-rGO) was synthesized via the Sonogashira–Hagihara coupling reaction and assembled into an electrochemical sensor for vanillin detection. Due to the enhanced electrical conductivity and electrocatalytic characteristics of CMP-rGO, the sensor demonstrated a low detection limit of 0.07 μM and a broad response range of 0.08–20 μM. Furthermore, this reusable sensor exhibited acceptable recoveries when evaluating vanillin in pharmaceuticals and human serum. This study offers technological assistance for the rapid detection of vanillin in pharmaceuticals and broadens the application of CMP-rGO.

Highly substituted naphthalene derivatives were prepared via palladium-catalyzed reaction of 5-(2-bromophenyl)pent-3-en-1-ynes with arylboronic acids. Typically, reaction of 3-bromo-4-(3-(4-chlorophenyl)-5-phenyl-1-(p-tolyl)pent-2-en-4-yn-1-yl)-N-methylaniline (1a) with PhB(OH)₂ in the presence of Pd(PPh₃)₄ as the catalyst under basic conditions provided 8-benzhydryl-7-(4-chlorophenyl)-N-methyl-5-(p-tolyl)naphthalen-2-amine (2a) quantitatively. Overall, 19 new naphthalene compounds were obtained by this methodology and their structures were characterized by spectroscopic methods. In addition, crystal structure of 2j was determined to confirm the structural details. Reaction pathway leading to the desired product is also discussed.