Ptolemy Journal of Chemistry (PJC)

The present study addresses the extraction of nanosilica (NPs) from sugarcane bagasse ash through a two-step process involving alkali extraction and acid precipitation. The following parameters affecting silica yield and purity were evaluated: ash:NaOH ratio, fusion temperature and time, reflux time, acid used in precipitation (type and concentration) and gelation pH. The synthesized NPs samples were characterized by conventional physical and chemical analysis techniques. The statistical analysis showed that ash:NaOH ratio was the factor with the greatest influence on the silica synthesis yield. The optimum conditions was obtained by 1:2 ash:NaOH ratio (w:w), fusion temperature of 300^∘C for 30 min, 1-h reflux, precipitation using 8 mol L⁻¹ sulfuric acid, gelation pH 4, resulting in 88% silica recovery and 96% purity. Silica prepared under optimized conditions was examined for removal of dyes from aqueous solution. The material showed efficient methylene blue and crystal violet adsorption with Langmuir adsorption capacity of 108.4 mg⋅g⁻¹ and 102.0 mg⋅g⁻¹, respectively. These results confirm that silica derived from sugarcane bagasse ash represents an effective and low-cost adsorbent for removing dyes from wastewater contributing to circular economy strategies and promoting sustainable waste management.

The prebiotic formation and persistence of carbohydrates remain central challenges in origin-of-life chemistry owing to their instability and structural diversity in aqueous environments. Among potential stabilizing agents, boron species—primarily boric acid and borate—exhibit a unique capacity to form reversible, stereoselective complexes with cis-diol-containing molecules, including sugars and low-molecular-weight polyols. Here we examine the coordination chemistry of boron–diol interactions and explore their implications for prebiotic chemical evolution. By preferentially stabilizing specific sugar configurations, particularly furanose forms, boron may bias the composition of prebiotic mixtures, acting as a primitive chemical “editor.” These dynamic interactions—encompassing mono- and diester formation, as well as higher-order assemblies—are modulated by environmental factors such as pH and evaporative concentration. We propose that boron-mediated complexation constitutes a form of thermodynamic selection that enriches biologically relevant carbohydrates, including ribose, while disfavoring less stable isomers.

We present a unified, set–theoretic framework that extends molecular graphs to hypergraphs and superhypergraphs via iterated power sets. We define Molecular Graphs, Molecular HyperGraphs, and Molecular SuperHyperGraphs, and develop four complements over them: Weighted, Rough, Neural, and Multipolar frameworks. We prove concise inclusion results—most notably, that the Weighted Molecular SuperHyperGraph strictly contains both Weighted Molecular HyperGraphs and (unweighted) Molecular SuperHyperGraphs—while preserving alternating–path distances under canonical embeddings. Compact examples (e.g., methane, ethanol, acetic acid) illustrate how atoms, bonds, functional groups, and higher–order motifs appear as vertices, hyperedges, and superedges under rank constraints. We also provide implementation–agnostic message–passing rules for variable–arity interactions, enabling property prediction and hierarchical analysis in chemistry and chemical biology. This paper is devoted to theoretical analysis, and it is hoped that quantitative studies by domain experts will be developed in future work.

For the first time, the chemical composition of essential oils obtained from the leaves and flowers of Mediterranean rosemary (Salvia rosmarinus) collected in forested areas surrounding Jerusalem has been investigated. Gas chromatographic analysis revealed that the essential oils are dominated by structurally unusual terpenoids containing a cyclobutane ring. A comprehensive survey of the literature further demonstrates that S. rosmarinus is a prolific natural source of cyclobutane-containing terpenes, with approximately 40 such compounds reported to date. These rare terpenoid frameworks are of particular interest due to their uncommon ring strain and distinct biosynthetic origin. In addition, available data on the biological activities of the major cyclobutane-containing terpenes are summarized, highlighting their antimicrobial, anti-inflammatory, antioxidant, and cytotoxic properties. Collectively, these findings underscore rosemary as a unique producer of cyclobutane terpenoids and emphasize the pharmacological potential of this rare class of natural products.

The concept of a classical structure provides a broad mathematical framework, whereas a Hyperstructure arises via the powerset construction, and an n-Superhyperstructure is obtained by iterating this construction n times. Intuitively, the n-th powerset corresponds to n successive applications of the powerset operator. Below, we recall the fundamental definitions and illustrate them with elementary examples. In the chemical sciences, various hyperstructural frameworks—such as Chemical Hyperstructures—have also been studied. In this paper, we introduce the notion of a Chemical Superhyperstructure and examine its foundational properties. We further extend the idea of a Weak Chemical Hyperstructure by defining the Weak Chemical Superhyperstructure via the Weak Superhyperstructure (SHv-Structure) framework, and provide an overview of its behavior. These constructions offer a concise and flexible means to represent hierarchical relationships in chemical systems.

The present study investigates the phytochemical composition and biopesticidal efficacy of bark extracts from four medicinal plants—Terminalia arjuna, Neltuma juliflora, Saraca asoca, and Cinnamomum verum—against the stored-grain pest Tribolium castaneum (Herbst). Bark samples were taxonomically authenticated, extracted using standardized protocols, and subjected to qualitative phytochemical screening, revealing abundant alkaloids, flavonoids, terpenoids, phenolics, and other secondary metabolites. GC–MS profiling, supported by retention time, fragmentation patterns, and library match scores, identified several bioactive constituents, with T. arjuna and N. juliflora displaying the highest diversity and peak abundance. Repellency and toxicity bioassays, conducted with three independent replicates, demonstrated a significant concentration- and time-dependent response. One-way ANOVA followed by LSD post-hoc analysis confirmed statistically significant differences among treatments, while probit analysis provided LC₅₀ values with 95% confidence intervals, establishing T. arjuna as the most potent extract. In-silico molecular docking further highlighted compounds such as ellagic acid, catechin, quercetin, and luteolin as strong binders to key insect enzymatic targets, showing interaction energies comparable to or exceeding those of the synthetic insecticide malathion. Collectively, the integrated chemical, biological, and computational evidence underscores the promise of T. arjuna and N. juliflora bark extracts as effective, biodegradable, and environmentally safe biopesticide candidates. The findings support further purification, SAR-guided optimization, and field-scale validation of the active compounds for sustainable pest-management applications.

A series of novel substituted benzaldehyde derivatives of 4-Amino-7H-pyrrolo[2,3-d]pyrimidine (4A7HPP), designated as compounds 1a–1d, were synthesized under microwave irradiation, providing a safe, cost-effective, and efficient alternative to conventional procedures. The condensation of 4A7HPP with hydroxybenzaldehyde analogues in DMF afforded the corresponding imine derivatives in high yields (71.54–85.02%) with reduced reaction time and solvent consumption. The synthesized compounds were characterized by ¹H NMR, FT-IR, UV–Vis spectroscopy, and elemental analysis, confirming the presence of characteristic azomethine (–CH=N–) and aromatic proton signals. The compounds exhibited significant antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa (MIC: 7.5–28 mm), surpassing the standard drug streptomycin. Notably, antifungal evaluation against Candida albicans and Saccharomyces cerevisiae demonstrated activity up to 2.5 times greater than fluconazole. Molecular docking studies performed against target proteins—S. aureus DHFR (PDB ID: 2W9H), E. coli DHFR (PDB ID: 1RX2), and C. albicans ERG11 (PDB ID: 5TZ1)—revealed stronger binding affinities for compounds 1b and 1d (−8.3 to −9.0 kcal mol⁻¹) compared with reference ligands, supported by low RMSD values (0.655–0.785 Å). Brine shrimp lethality bioassay indicated moderate cytotoxicity (LD₅₀: 3.50–8.50 × 10⁻⁴ M). ADME analysis suggested favorable pharmacokinetic profiles, high gastrointestinal absorption, and compliance with Lipinski’s rule of five. These results highlight compounds 1a–1d as potential lead molecules for the development of new antimicrobial and antifungal agents, warranting further biological and pharmacological investigations.

A series of novel 2-methyl-5-[2-(substituted)phenyl]-1,3,4-oxadiazole derivatives (6a–6i) was synthesized via a multi-step protocol starting from commercially available salicylic acid (1). The initial esterification of salicylic acid using thionyl chloride and ethanol at 80 °C for 12 h yielded ethyl 2-hydroxybenzoate (2), which was subsequently converted to 2-hydroxybenzohydrazide (3) upon treatment with hydrazine monohydrate in ethanol at 80 °C for 2 h. Acetylation of intermediate 3 with acetic anhydride afforded N’-acetyl-2-hydroxybenzoate (4), which was reacted with various halo compounds (4a–4i) to produce a series of N’-acetyl-2-(substituted)oxybenzohydrazides (5a–5i). These key intermediates were cyclized using triphenylphosphine, triethylamine, carbon tetrachloride, and acetonitrile at 100 °C for 1 h to furnish the final oxadiazole derivatives (6a–6i). The compounds were purified using appropriate chromatographic techniques and fully characterized by ¹H NMR, ¹³C NMR, FTIR, and mass spectrometry. Biological screening of the synthesized compounds revealed that several derivatives, particularly 6c, 6d, and 6g, exhibited promising antimicrobial and antioxidant activities. Notably, compound 6a demonstrated significant cytotoxicity against HeLa cancer cells. Molecular docking studies further supported the biological potential of the compounds, with 6e displaying a high docking score of –5.66 kcal/mol.

Shea butter is a natural moisturizer used to improve skin health. This study investigates its effects on skin barrier function, hy-dration, and lipid profile, using analytical chemistry methodologies. Trans-Epithelial Water Loss (TEWL), corneometry, im-pedance spectroscopy, and gas chromatography-mass spectrometry (GC-MS) were used to assess skin barrier function, hydra-tion, and lipid profile after shea butter application. Results show that TEWL decreased by 37.8% after 24 hours (p < 0.01), Skin hydration increased by 58% after 24 hours (p< 0.001). Impedance spectroscopy showed a 33% increase in skin imped-ance, GC-MS analysis revealed a balanced fatty acid composition in shea butter, ceramide profiling showed six subclasses, with Ceramide 1 and 2 being the most abundant. The results demonstrate shea butter’s efficacy in improving skin barrier func-tion, hydration, and lipid profile. The rapid decrease in TEWL and increase in skin hydration suggest immediate effects on skin lipids. Shea butter’s fatty acid composition contributes to its moisturizing and barrier-enhancing properties. This study provides evidence for the benefits of shea butter in maintaining healthy skin. Its natural moisturizing properties make it a valuable in-gredient in skincare products.

Medicinal plant’s quality and safety are becoming a great interest topic worldwide, especially due to contamination with heavy metals. The main objective of this study is to determine the phytochemical composition and quantify the concentration of heavy metals, trace and macro elements in fourteen medicinal plants purchased in the Central Market of San Salvador. Samples were dried and fractionated, subsequently digested and analyzed at first by phytochemical screening and then by atomic absorption spectrometry. The concentration of twelve elements was determined, only Matricaria chamomilla exceeded the established World Health Organization limit for Cd and Cu. Acourtia nudicaulis and Turnera diffusa exceeded the permitted concentration of Ni. The concentration of these elements must be inspected in medicinal plants sold in the informal markets of El Salvador to ensure the safety and quality. To our knowledge, this is the first study of heavy metals in medicinal plants conducted in El Salvador.