Molecules最新文献

It has been known since the 1990s that the introduction of a ferrocenyl-type substituent into compounds with proven biological activity can improve their properties. More recently, it was also shown that a carbon bridge connecting the two cyclopentadienyl rings in ferrocene derivatives could enhance the biological properties of the new compounds compared to those without them. However, the synthesis of ferrocenes with this additional linker, known as ansa-ferrocenes, is more difficult due to advanced synthetic protocols and the phenomenon of planar chirality in ring-substituted compounds. As a result, research into the formation of hybrids, conjugates and other ansa-ferrocene derivatives has not been widely conducted. This review discusses the potential biological properties of these units, covering scientific articles published between 1980 and 2024.

Of the three types of waste generated in beer processing, brewer's spent grain (BSG) is the most abundant and has a high potential for valorization. In this work, defatted BSG (DB) was subjected to an extraction process with subcritical water at different temperatures to obtain extracts rich in phenols and the cellulosic fractions, which were also purified by using hydrogen peroxide (H₂O₂). The results showed that the dry extracts obtained at 170 °C were richer in phenolics (24 mg Gallic Acid Equivalent (GAE) g^-1 DB), but with lower antioxidant capacity (71 mg DB·mg^-1 2,2-diphenyl-1-pikryl-hydrazyl). This extract also showed the highest antibacterial potential against L. innocua (80 mg·mL^-1) and E. coli (140 mg·mL^-1) than those obtained at lower temperatures. The purification of cellulose from the treated residues, using hydrogen peroxide, revealed that DB is a limited source of cellulose material since the bleached fractions showed low yields (20-25%) and low cellulose purity (42-71%), even after four bleaching cycles (1 h) at pH 12 and 8% H₂O₂. Despite this, the subcritical water extraction method highlights the potential of a simple process as a technological option to convert underutilized side streams like beer bagasse into added-value, potential ingredients for innovative food and pharmaceutical applications.

A total of twelve previously unreported isoindolin-1-one compounds, erinacenones A-L (1-12), were isolated from liquid cultures of the medicinal fungus Hericium erinaceus. Their structures were elucidated based on spectroscopic data analysis. The absolute configuration of 12 was determined by comparing its optical rotations with values reported in the literature. The most distinctive feature of these compounds is that their nitrogen atoms are connected to different parts of the special structure moieties. Among them, compounds 3 and 4, as well as 10 and 11, are two pairs of isomers differing only by a small change in the position of one double bond. Compounds 4 and 5 were found to show cytotoxic activities, with IC₅₀ values of 24.7 and 18.4 μM, respectively, against MCF-7 cell lines.

The current study investigates the influence of several R substituents (e.g., Me, SiH₃, F, Cl, Br, OH, NH₂, etc.) on the aromaticity of borazine, also known as the "inorganic benzene". By performing hybrid DFT methods, blended with several computational techniques, e.g., Natural Bond Orbital (NBO), Quantum Theory of Atoms in Molecules (QTAIM), Gauge-Including Magnetically Induced Current (GIMIC), Nucleus-Independent Chemical Shift (NICS), and following a simultaneous evaluation of four different aromaticity indices (para-delocalization index (PDI), multi-centre bond order (MCBO), ring current strength (RCS), and NICS parameters), it is emphasized that the aromatic character of B-substituted (B₃R₃N₃H₃) and N-substituted (B₃H₃N₃R₃) borazine derivatives can be tailored by modulating the electronic effects of R groups. It is also highlighted that the position of R substituents on the ring structure is crucial in tuning the aromaticity. Systematic comparisons of calculated aromaticity index values (i.e., via regression analyses and correlation matrices) ensure that the reported trends in aromaticity variation are accurately described, while the influence of different R groups on electron delocalization and related aromaticity phenomena is quantitatively assessed based on NBO analyses. The most relevant interactions impacting the aromatic character of investigated systems are (i) the electron conjugations occurring between the p lone pair electrons (LP) on the F, Cl, Br, O or N atoms, of R groups, and the π*(B=N) orbitals on the borazine ring (i.e., LP(R)→π*(B=N) donations), and (ii) the steric-exchange (Pauli) interactions between the same LP and the π(B=N) bonds (i.e., LP(R)↔π(B=N) repulsions), while inductive/field effects influence the aromaticity of the investigated trisubstituted borazine systems to a much lesser extent. This work highlights that although the aromatic character of borazine can be enhanced by grafting electron-donor substituents (F, OH, NH₂, O^-, NH^-) on the N atoms, the stabilization due to aromaticity has only a moderate impact on these systems. By replacing the H substituents on the B atoms with similar R groups, the aromatic character of borazine is decreased due to strong exocyclic LP(R)→π*(B=N) donations affecting the delocalization of π-electrons on the borazine ring.

At present, the effects of environmental electromagnetic irradiation on the metabolism of organisms have attracted extensive attention, but the mechanism is still not clear. D-glucose plays an important role in the metabolism of organisms. In this work, the change in the optical rotation of D-glucose solution under an electrostatic field is measured experimentally, so as to explain the mechanism of the electric field-induced biological effect. The experimental results show that the electrostatic field can alter the optical rotation of D-glucose solution at different temperatures. Under the different strengths of electrostatic field, the specific rotation of D-glucose solution increases at different temperatures; the maximum increase can reach 2.07%, but the effect of temperature and electric field strength on the rotation increment is nonlinear and very complex. Further, it turns out that the proportion of α-D-glucose in solution increases by up to 3.25% under the electrostatic field, while the proportion of β-D-glucose decreases by as much as 1.75%. The experimental study confirms that electrostatic field can change the proportion of two conformation molecules (α and β-D-glucose) in D-glucose solution, which can provide a novel explanation for the mechanism of the electric field-induced biological effect.

In this study, hydrogen production through the hydrolysis, ethanolysis, and methanolysis reactions of NaBH₄ using adipic acid as a catalyst was investigated for the first time. Adipic acid solutions were prepared with methanol and ethanol at concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 M. In these reactions, NaBH₄-MR (methanolysis) and NaBH₄-ER (ethanolysis) reactions were carried out at 30, 40, and 50 °C with NaBH₄ concentrations of 1.25%, 2.5%, and 5%. Hydrolysis reactions (NaBH₄-HR) were conducted at 0.1 M under the same conditions. In the ethanolysis and methanolysis reactions at 30 °C, total hydrogen conversion was achieved at 0.3 M, 0.4 M, and 0.5 M. However, in the hydrolysis reactions, total hydrogen production was only obtained at 50 °C. It was observed that in the NaBH₄-MR and NaBH₄-ER reactions, total hydrogen conversion could be achieved within 4-5 s. The utilization of adipic acid as a catalyst for hydrogen production from NaBH₄ through ethanolysis and methanolysis reactions is proposed as a highly efficient and fast method, characterized by impressive conversion rates.

Two series of polydentate N,O,S-ligands containing thiourea fragments attached to a p-cresol scaffold, unsymmetrical mono-acylated bis-amines and symmetrical bis-thioureas, are obtained by common experiments. It is observed that the reaction output is strongly dependent on both bis-amine and thiocarbamic chloride substituents. The products are characterized by 1D and 2D NMR spectra in solution and by single crystal XRD. A preliminary study on the coordination abilities of selected products is performed by ITC at around neutral media.

This study aimed to identify the inhibitory effect of Agastache rugosa essential oil (AREO) on the cariogenic properties of Streptococcus mutans, which causes dental caries and dental plaque formation. After extracting the AREO, their effects on the growth and acid production of S. mutans were examined. Furthermore, S. mutans biofilm formation was observed on the resin teeth surface. The effect on the expression of biofilm-related genes of S. mutans was measured using real-time PCR. AREO components were analyzed using gas chromatography (GC) and GC-mass spectrometry (MS). The growth and acid production of S. mutans were significantly inhibited at concentrations of 0.02 mg/mL or higher of AREO. At 0.04 mg/mL, inhibition was similar to that of the positive control, 0.1% NaF. AREO suppressed the expression of virulence factors such as gtfB, gtfC, gtfD, gbpB, SpaP, brpA, relA, and vicR at concentrations of 0.02 mg/mL or higher. As a result of GC and GC-MS analyses, the main components of AREO included estragole, limonene, and β-caryophyllene. These results suggest that A. rugosa may be a useful agent for inhibiting the cariogenic properties of S. mutans.

We developed dye-sensitized solar cells (DSSCs) using 1,5-carboxy-2-[[3-[(2,3-dihydro-1,1-dimethyl-3-ethyl-1H-benzo[e]indol-2-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]methyl]-3,3-dimethyl-1-octyl-3H-indolium and 1,3,3-trimethyl indolino-6'-nitrobenzopyrylospiran. The DSSCs incorporate photochromic molecules to regulate photoelectric conversion properties. We irradiated photoelectrodes adsorbed with SQ2/SPNO₂ using both UV and visible light and observed the color changes in these photoelectrodes. Following UV irradiation, the transmittance at 540 nm decreased by 20%, while it increased by 15% after visible light irradiation. This indicates that SPNO₂ on the DSSCs is photoisomerized from the spiropyran form (SP) to the photomerocyanine (PMC) form under UV light. The photoelectric conversion efficiency (η) of the DSSCs increased by 0.15% following 5 min of UV irradiation and decreased by 0.07% after 5 min of visible light irradiation. However, direct electron injection from PMC seems challenging, suggesting that the mechanism for improved photoelectric conversion in these DSSCs is likely due to Förster resonance energy transfer (FRET) from PMC to the SQ2 dye. The findings suggest that the co-sensitization of DSSCs by PMC-SQ2 and SQ2 alone, facilitated by their respective photoabsorption, results in externally responsive and co-sensitized solar cells. This study provides valuable insights into the development of advanced DSSCs with externally controllable photoelectric conversion properties via the strategic use of photochromic molecules and energy transfer mechanisms, advancing future solar energy applications.

The substitution of ingredients with Salmonidae, particularly Salmo salar, has led to widespread reports of financial losses and health risks globally, emphasizing the urgent need for the development of a rapid and precise method for species identification. The aim of the present study was to develop a novel method for the rapid screening of Salmonidae ingredients and the accurate detection of S. salar simultaneously using multiplex real-time PCR coupled with melting curve analysis. Specifically, primer sets specific for S. salar and Salmonidae were cross-confirmed. Moreover, the reaction system and conditions of a real-time duplex PCR were optimized, and the proposed methodology was verified, proving that the assay has good specificity and sensitivity. Clear and distinguishable melting peaks, with expected Tm values of around 80 °C (S. salar) and 84 °C (Salmonidae), were observed for twelve products, proving the presence of S. salar. However, four products were not derived from S. salar, but they could have belonged to another species within the Salmonidae family due to the presence of only one specific melting peak at a Tm value of about 84 °C. Therefore, the novel assay in the present study allows for the fast and accurate screening of Salmonidae ingredients and the detection of S. salar simultaneously.