Mohamed A. Al- Omar

Silicon quantum dots (Si-QDs) were utilized as a nano-catalyst in the one-pot synthesis of some new 1,8-dioxodecahydroacridine frameworks. The synthesized acridine derivatives undergo docking validation as anti-tubercular and anti-HIV agents.

Acarbose is a recognized inhibitor of [Formula: see text]-amylase and [Formula: see text]-glucosidase used in the treatment of diabetes mellitus. However, these established and therapeutically utilized inhibitors are also associated with numerous undesirable effects. Consequently, there is a need to develop safer therapies. Despite the wide range of biological activities of isatin and thiourea, their potential for [Formula: see text]-amylase and [Formula: see text]-glucosidase inhibition has been infrequently investigated. This study focuses on the synthesis and biological evaluation of isatin-based thiourea analogues (1– 18) for their [Formula: see text]-amylase and [Formula: see text]-glucosidase inhibitory activities. The structures of the synthesized analogues were confirmed using various spectroscopic techniques, including ¹ HNMR, [Formula: see text]CNMR, and HR-EIMS. All analogues exhibited excellent inhibitory potential against [Formula: see text]-amylase and [Formula: see text]-glucosidase enzymes, with IC[Formula: see text] values ranging from [Formula: see text] to [Formula: see text]M ([Formula: see text]-amylase) and [Formula: see text] to [Formula: see text]M ([Formula: see text]-glucosidase) compared to the standard drug acarbose (IC[Formula: see text] and [Formula: see text]M, respectively). Among these, analogues 2, 8, 11, and 17 demonstrated remarkable potency, significantly outperforming acarbose. Structure–activity relationship analysis revealed that different substitutions on the compounds significantly impacted their inhibitory potential. Additionally, in silico studies identified key structural features responsible for interactions with the active sites of [Formula: see text]-amylase and [Formula: see text]-glucosidase enzymes.

Charge-transfer (CT) reactions have attracted significant research interest due to their potential for developing novel CT materials with unique properties that are valuable in both fundamental research and materials science. This study examines the physical properties and optical band gaps of new CT complexes synthesized via interactions between two organic donors: carbonyldiimidazole (D1) and hydroxybenzotriazole (D2), and the acceptor 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ). Solid DDQ-D1 and DDQ-D2 complexes were prepared using two methods: liquid-liquid and solid-solid techniques, depending on the initial states of the reactants. The liquid-liquid method involved dissolving both components in a solvent, mixing their solutions in a specific ratio, evaporating the solvent, and isolating/purifying the resulting complex. The solid-solid method entailed grinding the components together to promote direct complex formation through intimate contact. Both approaches yielded the same 1:1 CT complexes between DDQ and each donor. The formation of these complexes is an exothermic, spontaneous process, as confirmed by elemental analysis, UV-Vis and FT-IR spectroscopy (which exhibited a characteristic n→π* transition, and physical parameters calculated using established equations. KEY WORDS: Charge-transfer reaction, DDQ acceptor, Organic donors, Physical parameters Bull. Chem. Soc. Ethiop. 2026, 40(9), 1809-1825. DOI: https://dx.doi.org/10.4314/bcse.v40i9.1

A series of 4-(2,5-dioxo-2,5-dihydro-1 H -pyrrol-1-yl)- N ′-[(substituted phenyl)methylidene]benzohydrazides ( BF 1–12 ) were synthesized and screened for  in vitro anticancer activity against K562 and KG-1 cancer cell lines.

Selenium nanoparticles have a wide range of applications in various fields, especially in the medical field. In this context, this manuscript aims to prepare and characterize selenium nanoparticles synthesized using pyrazole-based derivatives and investigate their potential biological activity as anti-diabetic and anti-Alzheimer's agents. The two selenium nanoparticles, Se-NPs+Py1 and Se-NPs+Py2, were characterized by a Fourier transform infrared (FTIR) spectrophotometer, ultraviolet-visible (UV-Vis) spectroscopy, and transmission electron microscopy (TEM). The results of in vitro biological evaluation show that the Se-NPs+Py1 (α-amylase = 49.98 ± 0.22% and α-glucosidase = 44.23 ± 0.22%) and Se-NPs+Py2 (α-amylase = 54.99 ± 0.27% and α-glucosidase = 49.24 ± 0.27%) possess potent activity against the α-amylase and α-glucosidase enzymes, as well as the acetylcholinesterase enzyme (Se-NPs+Py1 = 38.48 ± 0.21% and Se-NPs+Py2 = 38.06 ± 0.21%), more than the pyrazole-based derivatives Py1 (α-amylase = 37.62 ± 0.18%, α-glucosidase = 31.87 ± 0.18%, and acetylcholinesterase = 36.65 ± 0.20%) and Py2 (α-amylase = 41.62 ± 0.21%, α-glucosidase = 35.87 ± 0.21%, and acetylcholinesterase = 36.25 ± 0.20%). KEY WORDS: Nanotechnology, Nanoparticles synthesized, Transmission electron microscopy, α-Glucosidase enzyme, Native electrophoretic patterns Bull. Chem. Soc. Ethiop. 2026, 40(4), 879-892. DOI: https://dx.doi.org/10.4314/bcse.v40i4.11

Several linear and macrocyclic pentapeptide derivatives have been produced by coupling Nα-isophthalic acid 1 or Nα-isophthaloyl dichloride 2 with the appropriate sarcosine methyl esters. The corresponding Nα-isophthaloyl Sarcosyl-Sarcosine methyl ester 3 was developed by mixing 1 or 2 with sarcosine methyl ester. By hydrolyzing this with methanolic sodium hydroxide, the corresponding acid 4 was subsequently obtained. The corresponding tetrapeptide esters, Nα -isophthaloyl-bis-[Sarcosyl-Glycine ethyl ester], 5 and Nα -isophthaloyl-bis-[Sarcosyl -L-Phenylalanine methyl ester], 6, were developed by coupling the latter product 4 with another molecule of glycine ethyl ester or L-phenylalanine methyl ester. These compounds were subsequently hydrolyzed with methanolic sodium hydroxide to develop the corresponding acids, Nα-isophthaloyl-bis-[Sarcosyl–Glycine], 7 and Nα-isophthaloyl-bis-[Sarcosyl - L-Phenylalanine], 8. The corresponding cyclic pentapeptide methyl esters, Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl - Glycine]-L–Lys-(OMe), 9 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(OMe), 10, were obtained by cyclizing tetrapeptide acids with L-lysine methyl ester. Finally, the corresponding acids Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-Glycine]-L–Lys-(OH), 11 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(OH), 12, were obtained by hydrolyzing methyl esters 9 and 10 with 1 N methanolic sodium hydroxide or hydrazinolyzing them with hydrazine hydrate to produce the cyclohydrazide compounds, Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-Glycine]-L–Lys-(NHNH2), 13 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(NHNH2), 14. KEY WORDS: Amino acids, Linear peptides, Macrocyclic pentapeptides, Nα-isophthaloyl dichloride, Sarcosine Bull. Chem. Soc. Ethiop. 2026, 40(3), 667-678. DOI: https://dx.doi.org/10.4314/bcse.v40i3.13

A new series of cyclic pentapeptide candidates (7-9) was prepared via the coupling of Nα-isophthalic acid or dichloride with L-phenylalanine ester, yielding compound 3, Nα-isophthaloyl L-phenylalanine ester, which was hydrolyzed to the corresponding acid 4. Then, the Nα-isophthaloyl L-phenylalanine acid 4 was coupled with a second molecule of L-phenylalanine ester to afford tetrapeptide ester 5, which was hydrolyzed to acid 6. Moreover, cyclization of tetrapeptide acid 6, to give cyclic pentapeptide ester 7, acid 8, and hydrazide 9. The newly synthesized compounds (5-9) were characterized. KEY WORDS: Amino acids, Cyclopeptides, L-Phenylalanine, Nα-isophthaloyl-bis-peptides Bull. Chem. Soc. Ethiop. 2026, 40(2), 307-317 DOI: https://dx.doi.org/10.4314/bcse.v40i2.4

In the last two decades, selenium has been present in many fields, both industrially and biologically. The nano-selenium balls were prepared using the hydrothermal green method and characterized to ensure their crystallinity by using transmission electron microscopy/selected area electron diffraction (TEM/SAED) and Fourier transform infrared (FTIR). The prepared nanoparticles were used in the synthesis of aryl methylene bis-indole derivatives 3a-i by one-pot mixing of aromatic aldehydes and two moles of indole under solvent-free conditions at 60-70 °C. The prepared products were implemented as inhibitor ligands in the molecular docking study for α-amylase and α-glucosidase. The theoretical data obtained were compared with acarbose as a reference ligand, which encouraged us to measure the colorimetric in vitro anti-diabetic activity. Some bis-indole derivatives 3e, 3f, 3g, and 3i showed promising values and can be presented in vivo as anti-diabetic agents. KEY WORDS: Nano-selenium balls, Bis-indole derivatives, α-Glucosidase enzyme, Anti-diabetic agents, The energy score, Molecular docking Bull. Chem. Soc. Ethiop. 2026, 40(1), 23-34. DOI: https://dx.doi.org/10.4314/bcse.v40i1.3

Comprehensive assessment of bottled drinking water quality in Bahrain: trace contaminants, compliance, and public health implications.