BMC Chemistry最新文献

Presently, humanity is confronted with a range of diseases that have high death rates, especially those linked to cancerous growths. Several enzymes and proteins have been discovered as highly attractive targets for cancer treatment. The PARP family consists of 17 members and plays a crucial role in repairing DNA damage, which enables the survival of cancer cells. PARP-1 and, to a lesser extent, PARP-2 display above 90% activity in response to DNA damage, thereby distinguishing them apart from other members of the PARP family. Elevated levels of PARP-1 were observed in many types of tumor cells, such as breast, lung, ovarian, prostate, and melanomas. In an attempt to provide a future guide for developing selective inhibitors for PARP-1 over PARP-2 to minimize the resulting side effects from PARP-2 inhibitors, we constructed a structure-based virtual screening approach (SBVS). Firstly. A 3D pharmacophore was constructed based on the interaction of the selective inhibitor compound IV. After that, a database of nearly 450,000 phthalimide-containing inhibitors was screened through the validated pharmacophore, and 165 compounds were retrieved. The retrieved compounds were docked into the active site of PARP-1 where only 5 compounds MWGS-1-5 achieved a favorable docking score than the reference IV (-16.8 Kcal/mol). Redocking of the five compounds should have excellent selectivity for PARP-1 over PARP-2, especially compound MWGS-1. Further endorsement via molecular dynamics has proven higher affinity and selectivity for MWGS-1 towards PARP-1 over PARP-2, in which PARP-1- MWGS-1 and PARP-1- MWGS-1 achieved RMSD values of 1.42 and 2.8 Å, respectively.

Novel N-arylacetamides 2a–f were synthesized based on benzo[d]thiazole scaffold. The compounds 2a–c underwent Knoevenagel condensation through green synthetic method with different aromatic aldehydes and pyrazole-7-carbaldehydes delivered the respective arylidenes with efficient yields. Arylidenes 4 reacted with malononitrile affording the corresponding N-arylpyridones 11a–i. Moreover, the reaction of 2a–c with each of salicylaldehyde and 5-arylazo salicylaldehydes afforded the unexpected coumarins rather than quinolin-5-ones. The structure of coumarin 8 was confirmed by density functional theory (DFT) calculations using basis set B3LYP/6-311 G +  + (d,p) to obtain the suitable geometrical structure with molecular orbitals` energies revealing its planar structure and its agreement with experimental data. Besides, the antibacterial activity was tested against different bacterial strains revealing potent activity especially Gram-negative bacteria with excellent minimum inhibition concentration (MIC) value ranging from 31.25 to 250 µg/L. Additionally, compounds 2c and 4m showed enzyme inhibition against dihydrofolate reductase in Escherichia coli with greater potency (IC₅₀ for 2c = 3.796 µM, IC₅₀ for 4m = 2.442 µM) than the standard antibiotic trimethoprim (IC₅₀ = 8.706 µM). Investigation of the physicochemical properties of the newly compounds exhibited their better ADME properties that can be developed for the discovery of new antibacterial agents.

Graphical Abstract

A large set of antimalarial molecules (N ~ 15k) was employed from ChEMBL to build a robust random forest (RF) model for the prediction of antiplasmodial activity. Rather than depending on high throughput screening (HTS) data, molecules tested at multiple doses against blood stages of Plasmodium falciparum were used for model development. The open-access and code-free KNIME platform was used to develop a workflow to train the model on 80% of data (N ~ 12k). The hyperparameter values were optimized to achieve the highest predictive accuracy with nine different molecular fingerprints (MFPs), among which Avalon MFPs (referred to as RF-1) provided the best results. RF-1 displayed 91.7% accuracy, 93.5% precision, 88.4% sensitivity and 97.3% area under the Receiver operating characteristic (AUROC) for the remaining 20% test set. The predictive performance of RF-1 was comparable to that of the malaria inhibitor prediction platform (MAIP), a recently reported consensus model based on a large proprietary dataset. However, hits obtained from RF-1 and MAIP from a commercial library did not overlap, suggesting that these two models are complementary. Finally, RF-1 was used to screen small molecules under clinical investigations for repurposing. Six molecules were purchased, out of which two human kinase inhibitors were identified to have single-digit micromolar antiplasmodial activity. One of the hits (compound 1) was a potent inhibitor of β-hematin, suggesting the involvement of parasite hemozoin (Hz) synthesis in the parasiticidal effect. The training and test sets are provided as supplementary information, allowing others to reproduce this work.

For paediatric patients suffering from neurofibromatosis, Selumetinib (SEL) is the only approved drug. Here an original ecofriendly and high pace method is introduced using 96- microwell spectrophotometric assay (MW-SPA) to measure SEL content in bulk and commercial pharmaceutical formulation (Koselugo^® capsules). This assay was relied on in-microwell formation of a coloured charge transfer complex (CTC) upon interaction of SEL with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The complex was fully characterized by spectrophotometric and computational studies. The CTC exhibited an absorbance maximum (λ_max) at 440 nm. The ease of reaction occurrence, complex stability and its high absorptivity were proved by measuring its association constant (0.63 × 10² L/ mol), standard free energy change (-10.31 KJ/mol), molar absorptivity (ε) (3.78 × 10³ L/mol/cm), and the SEL: DDQ stoichiometric ratio (1:1). Establishments of the optimum values of the applied conditions in 96-well assay plate were refined regarding DDQ concentration, reaction time, temperature, and solvents. Validation of the assay was according to the ICH guidelines. The assay was linear in SEL’ concentrations ranged from 10 to 200 µg/well, with limits of detection and quantitation of 4.1 and 12.5 µg/well, respectively. Then, the assay was efficaciously adapted to accurately and precisely determine SEL content in bulk form and Koselugo^® capsules. The assay environmental safety was documented by three different comprehensive metric tools. Additionally, assessment of the assay’s rate demonstrated its high throughput, enabling the processing of large number of samples in pharmaceutical quality control laboratories. The successful development of this assay provides a valuable fast and green analytical tool for ensuring the quality control of SEL’s bulk form and capsules.

The study of green analytical chemistry has garnered significant attention in the context of mitigating global environmental contamination. In this study, we present two methodologies for environmentally friendly chromatography that enable simultaneous and specific determination of Saxagliptin (SAX), metformin (MET), and a pharmacopoeial impurity of MET known as melamine (MEL). The initial method employed in this study is High-Performance Thin Layer Chromatography (HPTLC), which utilized 60 F 254 silica gel-coated Mark HPTLC plates on aluminum sheets as the stationary phase. The developing system was made up of a mix of ethyl acetate: methanol: ammonia: glacial acetic acid in a ratio of 6:4:1:0.3 (v/v/v/v). The analysis was performed at a wavelength of 215 nm. The second method employed in this study is ultra-performance liquid chromatography (UPLC). In this method, a C18 column was utilized for the separation process. The mobile phase was made up of a mix of methanol and 0.01 M sodium dodecyl sulfate, with a pH of 3.3 achieved by adding orthophosphoric acid. The ratio of methanol to sodium dodecyl sulfate in the mobile phase was 70:30 (v/v). The flow rate of the mobile phase was established at a rate of 1.5 mL/min. The peaks found and recorded are resolved at a wavelength of 215 nm. The three analytes under investigation were successfully separated and assessed using the recommended protocols. Both methods were validated following the International Council for Harmonization (ICH) recommendations for assessing linearity, range, accuracy, precision, specificity, and robustness. Moreover, the environmental sustainability of the advanced methodologies The assessment has been performed using various instruments, such as the Analytical Eco-Scale, NEMI, GAPI, and AGREE. The utilization of these tools was implemented in order to perform a comprehensive assessment of the environmental sustainability of the methods, as well as to establish a comparison with previously documented approaches. This study was carried out to evaluate the potential environmental implications of the suggested methods and to determine their suitability for concurrent analysis of the examined pharmaceuticals in formula and quality control units.

Background

This work intended to assess the disinfection efficacy of hypochlorous acid (HA) and silver nanoparticles (AgNP) disinfectants in disinfecting the dental unit waterlines (DUWL) during comprehensive oral treatment and explore their potential applications in the oral medical environment. Methods: Firstly, AgNP solution was prepared and evaluated through X-ray diffraction (XRD), field emission transmission electron microscope (FE-TEM), and stability tests. Subsequently, 15 dental units were selected and randomly assigned to three groups, each receiving a different disinfection method. Specifically, one group (5 units) received HA disinfectant (HA group), one group (5 units) received AgNP disinfectant (AgNP group), and another group (5 units) received a combination of HA and AgNP disinfectant (HA + AgNP group). Bacterial counts before and after disinfection were compared and analyzed at four sites on the dental units: high-speed handpiece tubing, mouthwash, ultrasonic scaler, and three-way syringe.

Results

The growth of biofilm on the waterlines was observed using scanning electron microscopy (SEM) and laser confocal microscopy (LCM). The results indicated that AgNP solution was successfully prepared and demonstrated excellent stability. There was no significant difference in the average weekly number of patients treated across the three groups (P > 0.05). After disinfection, bacterial counts were significantly reduced in all groups. Compared to the HA and AgNP groups, the HA + AgNP group exhibited a markedly lower bacterial count, with statistical significance (P < 0.05). The compliance rates observed during the first disinfection and two weeks post-disinfection were slightly lower in the HA and AgNP groups compared to the HA + AgNP group, although no significant statistical difference was found (P > 0.05). SEM images revealed uneven biofilm plaques on the inner surface of the pipes prior to disinfection, embedded within a dense matrix, while the biofilm was visibly disrupted post-disinfection. LCM software analysis showed that, compared to the HA and AgNP groups, the HA + AgNP group had a significantly lower percentage of live bacteria on the biofilm post-disinfection (P < 0.05).

Conclusion

Compared to any single disinfectant regimen, the combined use of HA and AgNPs effectively inhibited bacterial growth and exerted a significant destructive effect on biofilms. Therefore, this combination is expected to be a viable option for disinfection of DUWL in the oral healthcare setting.

Clinical trial number

Not applicable.

An ecofriendly, effective, and selective spectrofluorimetric approach for natamycin analysis was developed using fluorescamine as a fluorogenic probe. Natamycin is the only topical ocular antifungal medication that is presently on the market for treating keratitis, conjunctivitis, and blepharitis caused by yeast and other fungi. Owing to its primary aliphatic amino group, natamycin can easily interact with fluorescamine resulting in the formation of the highly fluorescent diaryl pyrrolone derivative. The derivatization reaction was completed within very short time at room temperature in borate buffer solution (pH 7.6). The fluorescence intensity of the reaction product was monitored at 465 nm after exciting at 390 nm. The linearity range of the spectrofluorimetric method was 0.25–4.0 µg/mL of natamycin with limit of detection (LOD) of 0.082 µg/mL. The method was applied for the determination of the cited drug in pharmaceutical eye drops and artificial aqueous humor with high percentage recoveries and low relative standard deviations. In addition, the involved analytical procedure was green based on the results of the ecology scale scores.

The structural and electronic behavior of thiosemicarbazone (TSC)-based metal complexes of Mn (II), Fe (II), and Ni (II) have been investigated. The synthesized metal complexes were characterized using elemental analysis, magnetic susceptibility, molar conductivity, FTIR, and UV–Vis spectroscopy, the computational path helped with further structural investigation. The solubility test on the TSC and its complexes revealed their solubility in most organic solvents. DFT computational analysis was performed, and quantum reactivity parameters of the octahedral optimized complexes were calculated to describe the reactivity via the stability states of the synthesized complexes. FMOs map was generated to confirm similar findings and MEP analysis was applied to elaborate the important electrophilic and nucleophilic sites on the studied surfaces. Also, other important topological analyses such as electron localization function and reduced density gradient, to establish the favorable noncovalent interactions, were studied. In silico molecular docking approach was studied against the gram-positive bacteria Bacillus cereus to predict the potent inhibition behavior of the studied complexes. The findings summarized the inhibition prediction of the most interactive [NiL₂Cl₂], then [FeL₂Cl₂] complexes as confirmed by the binding energy values (− 7.1 kacl/mol and − 6.4 kacl/mol, respectively). Another In silico results, with gram-positive bacteria (S. aureus), estimated similar results of the experimental finding, where [MnL₂Cl₂] (− 9.2 kcal/mol) is the more effective predicted antibacterial inhibitor. Fluorescence microscopy was used to examine the inhibition of bacterial biofilm, and the DPPH assay was used to measure antioxidant activity, followed by an understanding of the behavior of the current complexes toward free radicals’ removal. The findings observed less aggregated bacterial strains covered with the studied complexes leading to less dense biofilm covering.

Trimethylamine-N-oxide (TMAO) is gut microbiota-derived metabolite, plays a critical role in human health and diseases such as metabolic, cardiovascular, colorectal cancer and, neurological disorders. Binding interactions between TMAO and serum albumins are crucial to understand the impact of TMAO on disease mechanisms. However, detailed insights into the interaction mechanisms, preferred binding locations, and conformational changes in BSA upon binding TMAO are still unclear. TMAO interacts with serum albumin in human body and thus, a model study of interaction for TMAO-BSA conjugate is presented in support of it. Decrease in absorbance intensity of protein upon interaction with metabolites reveals conjugate formation, while fluorescence spectroscopy indicate static quenching. Contact angle measurements further reveal the hydrophilic nature of the TMAO-BSA complex, while CD and FTIR support conformational changes in BSA upon binding but structure remain intact. Computational studies, such as molecular docking, molecular dynamics simulation and, MM/GBSA, confirm a stable complex with a binding energy of − 3.6 kcal/mol. These findings provide a foundation for understanding the pharmacodynamics and pharmacokinetics of TMAO and may aid in developing strategies for treating diseases, such as chronic kidney disease and neurological disorder where TMAO-serum albumins interaction are implicated.

Mn²⁺ is an essential cation extensively utilized in various industrial processes, including electrolytic manganese production, manganese dioxide manufacturing, and zinc processing. It also poses significant environmental challenges as a primary pollutant in Mn-containing wastewater and hazardous materials. Effective monitoring and control of Mn²⁺ in these processes are vital for improving resource conversion efficiency and minimizing pollutant production. However, the direct determination of high concentrations of Mn²⁺ remains challenging due to rapid reactions, which impede improvements in cleaner industrial production. Traditional detection method like potassium periodate spectrophotometry (PPS) method is limited to low concentrations and involve complex processes that contribute to secondary pollution. In this study, we evaluated the performance of four alternative methods—External Standard Calibration (EC), Area Under the Curve (AUC), Standard Addition (SA), and Multi-Energy Calibration (MEC)—for determining high-concentration Mn²⁺. The study found that the weak absorption characteristic of aqueous Mn²⁺ due to spin-forbidden transitions is advantageous for direct determination at high concentrations in its original valence state. By optimizing the optical path and wavelength, concentrations up to 50 g/L were detected, surpassing the PPS upper limit by 5000 times. Among the methods, EC demonstrated superior accuracy and precision, with a performance rate of 98.07% and a relative standard deviation of less than 1%. The EC method’s minimal time consumption and cost-effectiveness make it suitable for automation and integration into industrial systems for continuous, real-time monitoring. This research offers valuable insights into high-concentration Mn²⁺ determination using spectrophotometry, highlighting the EC method’s potential for real-time monitoring and its adaptability for large-scale industrial operations. The findings provide a substantial reference for the direct detection of other industrial components, promoting more efficient and environmentally friendly industrial practice.