Pure Form Research Articles

Szymanowski’s Third Piano Sonata and First String Quartet and the Artistic Theory and Practice of Stanisław Ignacy Witkiewicz: ‘Pure Form’, Subjectivity, and the Burlesque

Szymanowski’s Third Piano Sonata and First String Quartet and the Artistic Theory and Practice of Stanisław Ignacy Witkiewicz: ‘Pure Form’, Subjectivity, and the Burlesque

Exploring the Effects of Chirality of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl) phenyl]imidazolidine-2,4-dione and its Derivatives on the Oncological Target Tankyrase 2. Atomistic Insights.

Tankyrases (TNKS) are homomultimers existing in two forms, viz. TNKS1 and TNKS2. TNKS2 plays a pivotal role in carcinogenesis by activating the Wnt//β-catenin pathway. TNKS2 has been identified as a suitable target in oncology due to its crucial role in mediating tumour progression. The discovery of 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl) phenyl] imidazolidine-2,4-dione, a hydantoin phenylquinazolinone derivative which exists as a racemic mixture and in its pure enantiomer forms, has reportedly exhibited inhibitory potency towards TNKS2. However, the molecular events surrounding its chirality towards TNKS2 remain unresolved. Herein, we employed in silico methods such as molecular dynamics simulation coupled with binding free energy estimations to explore the mechanistic activity of the racemic inhibitor and its enantiomer forms on TNK2 at a molecular level Results: Favourable binding free energies were noted for all three ligands propelled by electrostatic and van der Waals forces. The positive enantiomer demonstrated the highest total binding free energy (-38.15 kcal/mol), exhibiting a more potent binding affinity to TNKS2. Amino acids PHE1035, ALA1038, and HIS1048; PHE1035, HIS1048 and ILE1039; and TYR1060, SER1033 and ILE1059 were identified as key drivers of TNKS2 inhibition for all three inhibitors, characterized by the contribution of highest residual energies and the formation of crucial high-affinity interactions with the bound inhibitors. Further assessment of chirality by the inhibitors revealed a stabilizing effect of the complex systems of all three inhibitors on the TNKS2 structure. Concerning flexibility and mobility, the racemic inhibitor and negative enantiomer revealed a more rigid structure when bound to TNKS2, which could potentiate biological activity interference. The positive enantiomer, however, displayed much more elasticity and flexibility when bound to TNKS2. Overall, 5-methyl-5-[4-(4-oxo-3H-quinazolin-2-yl) phenyl] imidazolidine-2,4-dione and its derivatives showed their inhibitory prowess when bound to the TNKS2 target via in silico assessment. Thus, results from this study offer insight into chirality and the possibility of adjustments of the enantiomer ratio to promote greater inhibitory results. These results could also offer insight into lead optimization to enhance inhibitory effects.

Revealing the Potential of Chios Mastic Gum and Its Constituents for Cosmetic Applications through Chemical Profiling and Biological Evaluation

Chios mastic gum (CMG), the resin of Pistacia lentiscus var. Chia, is a product with great ethnopharmacological and economic significance. This study attempts to investigate, for the first time, the activity of CMG, its fractions and isolated compounds against specific enzymes, which play pivotal roles in the degradation of proteins contained in skin connective tissue. Initially, crude CMG was subjected to extraction, fractionation and isolation through different chromatographic techniques to obtain the acidic and neutral fraction of terpenes. Additionally, the characteristic and major active triterpene acids of CMG, masticadienonic and isomasticadienonic acids (MNA, IMNA) were isolated in pure form. All samples were analysed by means of High-Performance Thin-Layer Chromatography (HPTLC) with four distinct development systems to obtain their constituents’ profile. Finally, samples were tested for their ability to inhibit the elastase and collagenase enzymes. According to our findings, for collagenase, a mixture of MNA and IMNA demonstrated the most potent activity with an IC50 value of 31.07 μg/mL, while for elastase CMG’s acidic fraction provided the most promising results with an IC50 value of 17.30 μg/mL. Overall, these results attempt to fill the gap in scientific knowledge about the use of CMG and its constituents in skincare and cosmetic products.

Chelator‐Assisted Precipitation‐Based Separation of the Rare Earth Elements Neodymium and Dysprosium from Aqueous Solutions

AbstractThe rare earth elements (REEs) are critical resources for many clean energy technologies, but are difficult to obtain in their elementally pure forms because of their nearly identical chemical properties. Here, an analogue of macropa, G‐macropa, was synthesized and employed for an aqueous precipitation‐based separation of Nd3+ and Dy3+. G‐macropa maintains the same thermodynamic preference for the large REEs as macropa, but shows smaller thermodynamic stability constants. Molecular dynamics studies demonstrate that the binding affinity differences of these chelators for Nd3+ and Dy3+ is a consequence of the presence or absence of an inner‐sphere water molecule, which alters the donor strength of the macrocyclic ethers. Leveraging the small REE affinity of G‐macropa, we demonstrate that within aqueous solutions of Nd3+, Dy3+, and G‐macropa, the addition of HCO3− selectively precipitates Dy2(CO3)3, leaving the Nd3+−G‐macropa complex in solution. With this method, remarkably high separation factors of 841 and 741 are achieved for 50 : 50 and 75 : 25 mixtures. Further studies involving Nd3+:Dy3+ ratios of 95 : 5 in authentic magnet waste also afford an efficient separation as well. Lastly, G‐macropa is recovered via crystallization with HCl and used for subsequent extractions, demonstrating its good recyclability.

Использование кремнийсодержащих удобрений как биостимуляторов при возделывании сахарной свеклы

Abstract. The current article is aimed at assessing the resistance of sugar beet plants of various hybrids to the phytotoxic effects of herbicides used both in pure form and in combination with silicon-containing ones. Methods. The research was carried out under the conditions of a field experiment, based on 4 repetitions in 2022–2023. Photosynthetic pigments in leaves were determined by optical density in an extract with 96 % ethanol. The influence of herbicides and biostimulants on the formation of plant mass, as well as the chlorophyll content in the leaves and the sugar beets yield of various hybrids were analyzed. Results. It was identified that the combined use of silicon-containing fertilizers “Mikrovit-6 Kremniy”, “Kelik Kaliy+Kremniy” in combination with herbicides contributed to an increase in the weight of one sugar beet plant after three herbicide treatments by 13–17 % depending on the hybrid compared to the option where only herbicides were treated, and the phytotoxicity of pesticides did not exceed 2.0–2.5 %. The sugar beet productivity depended on the toxicological load on the crop plants. In combination with the herbicides Mikrovit-6 Silicon and Kelik Potassium+Silicon, the total content of green pigment was 49–74 % higher than in plants stressed by herbicides, and chlorophyll a increased by 3.1–4.5 times. The domestic selection hybrids F1 Volna and F1 Skala were the most resistant to inhibition of photosynthesis processes. The scientific novelty of the current research lies in the fact that for the first time in the conditions of the Middle Volga region on leached chernozem, the most efficient silicon-containing fertilizers for reducing herbicidal stress of sugar beet plants have been identified. The identified results also contribute to the improvement of the photosynthesis process by increasing the concentration of chlorophyll, a greater average daily increase in biomass and an increase in the yield of sugar beet plants, as well as hybrids of domestic selection that are more stress-resistant to the negative effects of herbicides.

Эффективность поверхностного компостирования табачной пыли с использованием микробных смесей

Abstract. Tobacco dust is the main waste in the production of smoking products. The purpose is to study the possibility of tobacco dust utilization by surface composting together with microbial mixtures “Stimiks Kompost”, “Probioks Agro” and “Geostim”, directly in the field conditions, contributing to the restoration of soil fertility. Methods. In the years of research (2020–2021) tobacco dust was applied in doses of 5 and 8 t/ha in pure form and together with microbiological preparations. Scientific novelty. The method of using tobacco production waste as a fertilizer together with microbiological preparations is proposed. Results. It was established that for 30–60 days, tobacco dust application together with destructors, the content of basic nutrient elements in the soil increased: ammonium nitrogen form by 65–207 %, nitrate nitrogen by 83–225 %, available phosphorus by 21–107 %, exchangeable potassium by 80–194 %. Also Increasing of soil biological activity indicators was determined. The process of nitrifying ability of soil increases by 70–194 %, cellulose-destroying activity of microorganisms increases by 27–133 %, the amount of produced CO2 from soil increases by 61–129 %. The content of organic matter (humus) increases up to 4.2–5.5 % for the period of counting (4.0–4.7 % on the reference). Increase of moisture-holding capacity of soils in variants of experiment with tobacco dust and destructors was established (soil moisture for the period of research amounted to 18.4–25.5 %, in control – 17.1–18.7 %). The best results for surface composting of tobacco dust were obtained under wet conditions in 2021 (Hydrothermal coefficient (HTC) = 1.38), in 2020 HTC = 0.87. Mycological analysis revealed a decrease in soil infestation with pathogenic micro-mycetes in the variants of the experiment with tobacco waste. The increase in yield of bitter pepper (variety Baraniy rog) on the background of a mixture of tobacco dust and biodegraders amounted to 12–32 % (2020), seed cucumber (variety Dal’nevostochnyy 27) – 20–33 %.

An Efficient and Cost-effective Modified Carbon Paste Electrodes for Diltiazem Hydrochloride Determination in Tablets

Background and Objective: This study presented new sensitive and selective modified carbon paste (MCPE) potentiometric sensors modified with different ion pairs for the determination of the antihypertensive drug diltiazem hydrochloride (DTM-HCl) in biological fluids, pharmaceutical preparations, and in its pure form. Methods: Plasticizers, ion pair type, ion pair content, response time, temperature, and pH were just a few of the experimental factors evaluated that were found to affect electrode efficiency. The two electrodes that show the best sensitivity were prepared by mixing diltiazem-tetraphenyl borate (DTM-TPB) ion pair, graphite, and TCP or o-NPOE as a plasticizer. Result: Over the concentration ranges of 1.0x10-5–1.0x10-2, the produced electrodes I and II demonstrated monovalent Nernstian responses of 55.7±0.902 and 57.6±0.451 mV decade-1. The selectivity property of the suggested electrodes was used to study the interference ions. The concentration of DTM-HCl in pharmaceutical formulations and biological fluids was measured using these modified electrodes. During the validation procedure, metrics like linearity, accuracy, precision, limit of detection, limit of quantification, and specificity were used. Conclusion: The obtained results showed good agreement with the HPLC technique as indicated by the F and t-test values and can conclude the possibility of using this potentiometric method in the routine analysis of DTM-HCl.

Enhancement of sensitivity for moxifloxacin spectrofluorimetric analysis through photoinduced electron transfer inhibition. Green assessment with application to pharmaceutical eye drops

A green, simple, rapid, selective, and highly sensitive fluorimetric protocol has been established for quantitative analysis of the antibacterial drug moxifloxacin in its pure form and pharmaceutical dosage form. Owing to photoinduced electron transfer, moxifloxacin exhibits low native fluorescence in neutral media. Based on that, the developed fluorimetric protocol depends on inhibiting the photoinduced electron transfer effect of the nitrogen atom presented on the pyrrolidine ring in moxifloxacin by suitable adjusting of pH of the medium surrounding it, leading to its protonation. It is simply achieved by using 0.5 M acetic acid. This protonation enhances the native fluorescence of moxifloxacin, turning it into a stronger one. This fluorescence was measured at 498 nm after excitation at 295 nm with a linearity range from 10 to 60 ng mL−1 and a high correlation coefficient value of 0.9998. The fluorimetric approach could be applied for moxifloxacin detection with a limit of 0.89 ng mL−1 and a quantification limit of 2.69 ng mL−1. The developed method has been validated according to ICH guidelines, indicating high accuracy and excellent precision. Furthermore, the developed fluorimetric protocol was applied successfully for moxifloxacin analysis in pharmaceutical eye drops. As a result, the proposed protocol could be easily applied for quality control of moxifloxacin in different laboratories all over the world.

Derivative spectrophotometric method for simultaneous determination of ascorbic acid and folic acid in the pharmaceutical formulation; Comparative greenness assessment

Ascorbic acid and folic acid are frequently included together in multivitamin pharmaceutical products due to their complementary roles in maintaining human health. The quality and efficiency of supplements can vary depending on the manufacturer and the specific ingredients used, which are vital factors to consider. This research presents the development and validation of a simple, sensitive, accurate, and environmentally friendly derivative spectrophotometric technique utilizing the zero-crossing method for the simultaneous determination of ascorbic acid and folic acid, both in their pure form and in pharmaceutical formulations. The derivative spectrophotometry technique demonstrated measurable amplitude and substantial linearity for both analytes. At the zero-crossing points of folic acid (249.6 and 281 nm), ascorbic acid showed a measurable amplitude with a linear range of 0.17–12.0 μg/mL and 0.37–12 μg/mL, and detection limits of 0.057 μg/mL and 0.121 μg/mL, respectively. Conversely, folic acid displayed an observable amplitude at the zero-crossing point of ascorbic acid (265.6 nm) with a linear range from 0.26 to 15.0 μg/mL and a detection limit of 0.088 μg/mL.The greenness of the proposed derivative spectrophotometric method was evaluated using the White Analytical Chemistry (WAC) framework and the Green Analytical Procedure Index (GAPI). The method scored highly in both evaluations, confirming its minimal environmental impact and alignment with the principles of Green Analytical Chemistry. The GAPI assessment highlighted low environmental and health risks throughout the analytical process, making this method a green and sustainable choice for the simultaneous determination of ascorbic acid and folic acid. The method was successfully applied to synthetic laboratory mixtures and formulated tablets, showing excellent precision, accuracy, and recovery, while also being environmentally friendly.

Facile, eco-friendly and sensitive fluorimetric approach for detection of chlorpromazine: Application in biological fluids and tablet formulations as well as greenness evaluation of the analytical method.

Monitoring antipsychotic drugs in biological fluids, such as human serum and urine, is important for ensuring the safety and efficacy of psychiatric treatments. This process helps maintain therapeutic drug levels, minimize side effects, and optimize patient well-being. Chlorpromazine (CZ) is a widely prescribed antipsychotic drug used for conditions like schizophrenia, bipolar disorder, and acute psychosis. Almost all existing sensing techniques for CZ are either insensitive spectrophotometric methods or involve long and complex chromatographic procedures, limiting their routine use. In this work, we introduce a facile, green, and sensitive fluorimetric strategy with high reproducibility for detecting CZ in its pure form, tablet formulation, and spiked human plasma and urine without the need for derivatization reactions. The proposed method relies on the inhibition of the intramolecular photoinduced electron transfer (PET) effect by using 2.0 M acetic acid. This approach enables the linear detection of CZ from 3.0 to 600 ng/mL with remarkably low quantitation and detection limits of 1.51 and 0.49 ng/mL, respectively. Moreover, the developed method's greenness was evaluated.

Welfare regimes of European countries and their development in the context of membership in the European Union

Welfare regimes represent potential approaches to the implementation of redistributive policies worldwide. In European countries, several significant regimes have been identified, including the Conservative, Southern, Social Democratic, Liberal model, the Post-Communist European model, and the Model of the Former USSR. The present study focused on identifying the welfare regimes of EU members and candidate countries and examining whether shifts between these regimes occur over time. The k-means method was employed, generating a different number of clusters for two observed periods: 2013 and 2022 on the sample of 27 member and 4 candidate countries and 2023 on the sample of 27 member countries of EU. The input variables consisted of redistributive indicators focusing on income inequality and the risk of poverty. The analysis results confirmed that countries transitioned between regimes in all observed periods. In the mixed group of member and candidate countries, the number of clusters decreased from five to two. For member countries in 2023, the number of clusters was three, mainly due to the worsening risk of poverty in some countries. Notably, none of the clusters represented a pure form of the originally defined welfare regimes. A significant finding of the study was that all observed EU candidate countries have shifted towards the redistributive policies of EU member states. This shift was noted towards regimes of geographically proximate countries. Within the member countries, however, the adopted measures have also lead to the negative phenomenon of mutual distancing of social regimes.

PHYSICOCHEMICAL CHARACTERISATION OF SUVARNA BHASMA AND SUVARNA PRASHA USING ADVANCED TECHNIQUES

Background: Suvarna Prashana is an ancient Indian practice that boosts immunity, intelligence, memory, complexion, and virility and prevents infections in children. However, the characterisation of the drug is very limited. Material and Method: In this study, the physicochemical characterisation of Suvarna Bhasma is done with Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive Xray Analysis (EDAX ), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Suvarna Prash containing 15 mg of Suvarna Bhasma mixed with 0.25 ml of ghee and 0.75 ml of honey is characterised with Fourier Transform Infrared Spectroscopy (FTIR) with Suvarna Bhasma. Results: SEM revealed that gold particles of Suvarna Bhasma ranged from 27 nm - 8.1 µm and formed spherical aggregates of varied sizes with rough surfaces. EDAX suggested that Suvarna Bhasma contained Gold (86.3%), Oxygen (3.14%), and Carbon (10.52%). TEM reported that the particle size ranged from 2.2 to 18.9 nm, which existed in polycrystalline form as suggested by XRD. XPS confirmed the elemental state of gold Au(0), Silver-Ag +oxidation state, Carbon C-C, C=O, and C-N, where carbon is bonding with carbon, oxygen and nitrogen. FTIR revealed that Suvarna Bhasma alone had a single functional group of alkynes. When Suvarna Bhasma was triturated with honey and ghee, many functional groups were added to Suvarna Bhasma, i.e. fats, carbohydrates and amino acids. Conclusion: In this novel study, FTIR of Suvarna Prasha is reported for the first time, and it can be used as a fingerprint for drug identification. Also, it proves that Suvarna Bhasma, used in the current study, is a pure form of gold without heavy metals like mercury.

The effects of Staphylococcus aureus protein a (SpA) on the expression of inflammatory cytokines in autoimmune patients and their probable immune response modulation mechanisms

The recombinant Staphylococcal protein A (SpA) is widely used in biotechnology to purify polyclonal and monoclonal IgG antibodies. At very low concentrations, the highly-purified form of the protein A can down-regulate the activation of human B-lymphocytes and macrophages which are the key cells in determining autoimmune diseases. In the present study, the efficiency of three different forms of protein A, including native full-length SpA, the recombinant full-length SpA, and a recombinant truncated form of SpA on the reduction of 4 inflammatory cytokines, including IL-8, IL-1β, TNF-α, and IL-6 by peripheral blood mononuclear cell (PBMCs) were studied and compared to an anti-rheumatoid arthritis commercial drug, Enbrel. The recombinant proteins were expressed in E. coli and the native form of SpA was commercially provided. PBMCs were obtained from adult patients with active rheumatoid arthritis (RA) and healthy control donors. Then, the effect of different doses of the three pure forms of SpA in comparison with Enbrel was investigated by analyzing the expression of selected cytokines using ELISA. The results showed that the truncated form of recombinant SpA significantly reduced the expression of cytokines more effectively than the other full-length formulations as well as the commercial drug Enbrel. In silico analysis shows that in the truncated protein, as the radius of gyration increases, the structure of IgG-binding domains become more open and more exposed to IgG. To summarize, our findings indicate that the truncated form of protein A is the most efficient form of SpA as it significantly decreases the secretion of evaluated cytokines from PBMCs in vitro.

Utilizing erythrosine B absorption spectrum shifts for quantitative determination of octreotide and bromocriptine in their pure forms and pharmaceutical formulations. Evaluation of the method greenness

In the present study, two drugs for treating acromegaly are investigated which are either synthetic growth hormone inhibiting hormone (GHIH) or dopamine receptor agonist. Octreotide (OCT) and bromocriptine (BCT) were quantified with a quick, simple, and sensitive spectrophotometric approach in their authentic forms and commercial dosage forms. This approach was based upon formation of ion pair complex between erythrosine B and investigated drugs in an aqueous buffered solution. For OCT determination the higher sensitivity was obtained using ΔA at 525 nm. On the other hand, BCT was estimated using the absorbance at 556 nm. Under optimal conditions for the reaction, construction of calibration curves were performed within concentration range of 0.4–4 µg ml−1 for OCT and 1–9 µg ml−1 for BCT with with low detection limits (0.094 and 0.235 µg ml−1) and low quantitation limits (0.29 and 0.71 µg ml−1) for OCT and BCT respectively. The developed approach was assessed for linearity, accuracy, precision, limits of detection, and limits of quantitation in compliance with ICH validation recommendations. The suggested approaches demonstrated good linearity, as evidenced by determination coefficients (r2) of 0.999 with a slope 0.14 for OCT and 0.9989 with a slope 0.06 for BCT. Additionally, the environmental friendliness of the investigated method was assessed with some of the recent green analytical chemistry metrics.

Novel Synthesis and Biophysical Characterization of Zinc Oxide Nanoparticles Using Virgin Coconut Oil.

One of the primary concerns in the field of green synthesis of nanoparticles (NPs) utilizing plant materials is the scarcity of high purity, challenges in achieving large-scale production, and limited global accessibility. Hygienic preparation and safe storage of plant extracts are also considerable challenges in this field. So, an investigation was started to overcome these limitations. Virgin coconut oil (VCO) in its purest form is available commercially all over the world. Also, it has high medicinal value with excellent biomedical applications. Very limited work has been reported on oils as bio reducers and stabilizers. In those reports, they used a few chemicals as mediators in the processes of synthesis and cleaning. So, to the best of our knowledge, for the first time, zinc oxide (ZnO) NPs were synthesized using VCO as a reducing and capping agent with zero chemical mediators. A comprehensive investigation of the structural, microstructural, and optical properties was reported. X-ray diffraction confirms the formation of VCO-ZnO NPs with an average crystallite size of 32.81 nm in a hexagonal structure. UV characteristics confirm quantum confinement through a well-defined SPR near 223 nm with fwhm of 67 nm and a direct band gap at 3.96 eV. FTIR reveals the capping of VCO through carboxylic functional groups, particularly the -COO- group of coconut oil at 1770 cm-1 with a shift of about 30 cm-1 compared to plain VCO. TEM confirms the polycrystalline nature with nearly spherical and 10-22 nm particle size. The zeta potential of -15.4 ± 5.0 mV signifies the stability and antiagglomeration properties. FESEM with EDS results confirms morphological excellence, the purity level of synthesized NPs (99.5%), and the prominent scalability of NPs (84.38% yield). Finally, as-synthesized VCO-ZnO NPs showed very good antioxidant (IC50 78.991, 51.464, and 4.677 μg/mL in DPPH, ABTS, and FRAP assays, respectively), anti-inflammatory (IC50 22.42 μg/mL in protein denaturation), antimicrobial (MIC 0.156 mg/mL for Pseudomonas and 0.316 mg/mL for S. aureus), and antidiabetic properties (IC50 88.45 and 147.67 μg/mL for α-amylase and α-glucosidase assays, respectively).

Enhancement of Valsartan Solubility by Amorphous solid Dispersion Ternary System: An Optimization and Characterization

Valsartan has poor water solubility, particularly at a pH below 5 due to its pH-dependent solubility. This limits its bioavailability. To enhance the solubility and dissolution rate of valsartan solid dispersion, we prepared it using the spray drying technique in a ternary system. Kollidon VA64 and Kolliphor P407 were utilized in various ratios for its preparation. Drug solubility, crystallography, and dissolution of Val-ASD were evaluated to examine the effect of formulation on its physicochemical characteristics. The molecular interactions between the drug, polymer, and surfactant, as well as amorphization, were analysed using FTIR, DSC, and XRD. Optimisation was conducted utilising the full factorial design approach with a confidence level of 95%. Valsartan was prepared as a solid dispersion that showed a 39-fold increase in solubility compared to its pure form. Furthermore, the formulation was found to accelerate the rate of dissolution. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) profiles indicated complete amorphization, while the Fourier transform infrared (FTIR) profile displayed hydrogen bonding and hydrophobic interactions between the drug and matrix, which collectively contribute to its enhanced characteristics. Solubility and dissolution were improved in a dependent manner with respect to Kollidon VA64 and Kolliphor P407.

Sodium salicylate as a green fluorescent probe for ultrasensitive determination of vonoprazan fumarate via fluorescence switch off strategy; greenness assessment

A green, simple and sensitive spectrofluorometric approach for determining vonoprazan fumarate in bulk and pharmaceutical dosage form by turning off the fluorescence of sodium salicylate is developed. The addition of vonoprazan fumarate reduced linearly the fluorescence intensity of 0.4 mM sodium salicylate at λem 408 nm and at λex 330 nm. The approach was found to be linear in the 50.0–3000.0 ng/mL range. The limits of detection and quantification were 10.97 and 33.23 ng/mL, respectively. The presented method proved its suitability in determination of vonoprazan fumarate in its pure and pharmaceutical dosage form. This method employs water as the exclusive solvent and utilizes safe reagents, evaluated using the Analytical Eco Scale, Green Analytical Procedure Index (GAPI), and carbon footprint. In contrast, previous methods relied on toxic reagents and required extended heating times, resulting in higher environmental impact. The novel method not only enhances analytical efficiency but also aligns with green chemistry principles, offering a sustainable solution for routine pharmaceutical analysis.

Spectrophotometric determination of Meloxicam in Pure Form and its Pharmaceutical Formulation following azo dye formation with 4-nitroaniline

A fast, cheap, and straightforward spectrophotometric method has been proposed to determine meloxicam (MEL) in its pure form and pharmaceutical formulation. The technique involves diazotizing the (NH2) group in 4-nitroaniline with NaNO2 followed by a reaction with meloxicam to produce a stable and colored complex in a basic medium. This complex demonstrates maximum absorbance at 514 nm. The developed method's linearity ranges from 2.0 - 25 μg mL-1, and the molar absorptivity is 1.5989×104 L mol-1 cm-1. The RSD% is lower than 1.55%. Additionally, the limit of detection (LOD) is 0.2019 μg mL-1. The method successfully determines the pharmaceutical preparation containing meloxicam (Loxim tablets) with a recovery rate of no less than 97.9%.

Stability-indicating liquid chromatographic method development and validation for quantification of trifarotene in pure and topical drug product

BackgroundTrifarotene is effective for treating acne and other skin issues. To ensure its quality and meet regulatory standards, a reverse phase liquid chromatography (RP-LC) stability-indicating method was developed and validated for its quantification in pure and topical dosage forms. An isocratic elution chromatographic method was employed, using an octadecylsilyl silica gel-packed column (150 mm × 4.6 mm, 3 µm particle size). The mobile phase was a mixture of phosphate buffer and acetonitrile (40:60 v/v). Chromatographic conditions included a flow rate of 0.5 mL/min, column temperature of 40 °C, detection at 265 nm, and injection volume of 20 µL.ResultsThe developed analytical method reports the retention time of trifarotene 11.2 min, higher theoretical plate count, asymmetric peak, and good resolution between the peaks of trifarotene, phenoxyethanol, and environmentally generated impurities.ConclusionThe analytical method has been found to be linear, accurate, robust, specific, and selective for impurities produced during forced degradation studies. The proposed analytical method can be utilized for routine pharmaceutical analysis of trifarotene to judge its quality and safety.

Collective Asymmetric Synthesis of Thiosilvatins

Thiosilvatins are a family of biologically active sulfenylated diketopiperazine natural products. The first members were reported over 40 years ago, but total synthesis of a thiosilvatin has remained elusive. Here, we describe the first, collective, synthesis of the parent epidithiodiketopiperazine (–)‐dithiosilvatin and ten related thiosilvatins. Several of the targets are structurally revised. A catalytic asymmetric sulfenylation of triketopiperazines efficiently controls absolute configuration at the thioaminal units. Further synthetic highlights include a diastereoconvergent installation of the requisite cis‐orientation of the sulfur atoms and a tandem epidisulfide formation/O‐prenylation under mild Mitsunobu conditions. The described methods for late‐stage diversification of sensitive bis(methylthio)diketopiperazines offer a blueprint for systematically exploring this interesting 3D‐pharmacophore in stereochemically pure form.