Raed A. Al-Qawasmeh

The extraction of essential oil from agricultural resources continues to be a challenge in the context of purity, the integrity of delicate compounds, and low yield. In the current study, a new distillation protocol, involving the use of Glucose–Citric Acid-based Natural Deep Eutectic Solvent (NaDES), has been developed and optimized through artificial intelligence (AI)-based models for enhanced recovery of Ocimum basilicum L. essential oil (OBEO). The NaDES mixture was prepared at various compositional ratios and customized through statistical tools of RSM as well as AI-based models (ANN) to optimize the recovery and chemical composition of OBEO. The physicochemical properties of the prepared NaDES were studied at 5–50% molar ratios of water, which revealed a pH drift of 1–2.5, a viscosity of 1244–5.21 mPa.s, and a density of 1.55–1.22 g/cm³. The maximum yield of OBEO (41.00 ± 0.27 mL/Kg of fresh aerial material) was obtained with the extracting solvent containing 31.6% NaDES applied with 7.18 mL/g solvent-to-solid ratio at 70 °C and 210 min of distillation time. Interestingly, the chemical composition of OBEO obtained through the test protocol was more diverse in chemical nature in comparison to the control (hydrodistillation) when studied through GC-MS analysis. Moreover, NaDES-based OBEO demonstrated potent broad-spectrum antimicrobial activity, antioxidant activity (90.36% inhibition of DPPH^⸰), and notable mosquito repellent activity (RC₅₀ = 407 µL). These findings indicate that Glucose–Citric Acid-based NaDES in combination with water can distill OBEO more efficiently for its application in food and pharmaceutical industries.

3-(Benzo[d][1,3]dioxol-5-yl)-2-(pyridin-3-yl)thiazolidin-4-one, a novel derivative of 1,3-thiazolidin-4-one, was synthesized by Schiff base formation followed by cyclocondensation with thioglycolic acid. The structure of the synthesized compound was characterized by spectroscopic techniques, including NMR, GC-MS, and HRMS. The molecular structure was unambiguously established by single-crystal X-ray diffraction. The compound crystallizes in the monoclinic crystal system with space group C2/c (No. 15) and unit-cell parameters a = 14.69 Å, b = 9.615 Å, c = 22.198 Å, and β = 98.49°. The molecular geometry reveals that the sulfur atom of the 1,3-thiazolidin-4-one ring is significantly out of the plane of the remaining ring atoms and adopts a puckered conformation. In the solid state, the supramolecular architecture is stabilized by a combination of interactions, including hydrogen bonding and weak π···π interactions. Furthermore, Hirshfeld surface analysis and two-dimensional fingerprint plots were used to quantify the intermolecular interactions, revealing that H···H (32.4%), O···H/H···O (20.2%) C···H/H···C (18.1%) contacts make the most significant contribution to Hirshfeld surfaces. Energy framework calculations indicated that dispersion energy, arising mainly from π···π interactions, is the dominant contributor to stabilization of the crystal packing.

Cysteinyl leukotrienes (CysLTs), derived from arachidonic acid, play a crucial role in regulating inflammation. We synthesized a novel series of CysLT2 antagonists containing the benzo[d][1,3]dioxole moiety using a synthetic strategy based on the Mannich reaction, resulting in the formation of 4-(benzo[d][1,3]dioxol-5-yloxy)-N,N-2-yn-1-amine. The structures of the synthesized compounds were characterized through NMR and HRMS analyses, and a plausible reaction mechanism was proposed. The inhibitory activities of all new compounds against CysLT2 were evaluated in vitro. Among them, compounds 4d and 4g exhibited the most potent inhibitory effects, with IC₅₀ values of 18.7 μM and 15.5 μM, respectively. These findings were further supported by molecular docking studies, which highlighted the binding interactions of these compounds within the kinase’s active site. Graphical abstract:

A series of new pyridine-1,2,4-triazole-tagged 1,2,3-triazole hybrid molecules were obtained. The new compounds were synthesized via click chemistry of 1,2,4-triazole-3-thiopropargyl compounds and various azides. All compounds were fully characterized through their spectroscopic analyses. Furthermore, cytotoxic activity was assessed by screening against three cancer cell lines including human colon carcinoma (HCT116), human cervix carcinoma (HeLa) and human breast adenocarcinoma (MCF7). In addition, antimicrobial assessment against one gram-positive (Staphylococcus aureus ATCC 29,213), two Gram-negative bacteria (Sarcina lutea and Escherichia coli ATCC 25,922) and one fungal (Candida albicans NRRL Y–477) microorganism‏.‏ Molecular docking studies of the synthesized compounds against DNA gyrase were used to identify their binding ability to the target enzyme. The best docked molecules unveiled binding affinities to the target ranging from −9.5 to −8.8 kcal mol⁻¹. The adsorption, distribution, metabolic, excretion, and toxicity (ADME/Tox) and drug-likeness analyses of the best docked compounds were evaluated using in silico techniques. Based on in vitro and in silico findings, these pyridine-1,2,4-triazole-tagged 1,2,3-triazole hybrid molecules may be helpful in designing potential antimicrobial drug candidates.

C₂₀H₂₈N₂OS, triclinic, P1̄ (no. 2), a = 6.7356(10) Å, b = 10.8739(15) Å, c = 13.245(2) Å, α = 75.580(7)°, β = 78.612(7)°, γ = 87.564(7)°, V = 921.0(2) ų, Z = 2, R _gt(F) = 0.0796, wR _ref(F ²) = 0.2666, T = 100(2) K.

A new chemical library based on the hybridization of cholic acid with the heterocyclic moiety 1,3,4-oxadizole was synthesized, and tested for antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi. Among the synthesized compounds, the most potent derivatives against S. aureus were 4t, 4i, 4p, and 4c with MIC values between 31 and 70 µg/mL, while compound 4p was the most active one against Bacillus subtilis with a MIC value of 70 µg/mL. Interestingly, compounds 4a and 4u exerted selective activity against Gram-positive bacteria. The synthesized compounds showed good activity against A. fumigatus and C. albicans and compound 4v exhibited selective activity against fungi only.

A new series of aminoacetylenic nitroimidazole piperazine hybrid compounds were prepared via three-component reaction. Mannich-type reaction was utilized to couple the nitroimidazole containing propargylic moiety with secondary amines and formaldehyde in the presence of Cu (I) catalyst. The newly synthesized molecules 10a–10w, were characterized an ambiguously through NMR and mass spectrometry. The prepared compounds were assessed in vitro for their antibacterial activity against selected gram-positive and gram-negative bacteria. All of the compounds had shown insignificant activities toward gram-negative bacteria. While compounds 10m, 10q, 10s and 10t had shown moderate activities against the gram–positive bacteria Staphylococcus aureus, Bacillus subtilis and against fungi Escherichia coli and Proteus vulgaris.