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Background and Objectives: Syzygium (the family Myrtaceae) is a well-known genus in the field of food chemistry and medicinal purposes. The current study aims to provide a chemical analysis of essential oils from the fresh leaves of two Vietnamese Syzygium species Syzygium oblatum (Roxb.) Wall. ex Steudel and S. abortivum (Gagnep.) Merr. & L.M.Perry. Methods: Chemical compounds in essential oils were identified using GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry) analysis. The broth microdilution method was used for the antimicrobial assay. Docking stimulation aided experimental results. Results: (E)-Caryophyllene (27.89%), α -selinene (18.34%), β -selinene (17.48%), and α -pinene (5.20%) were identified to be the main compounds in S. oblatum leaf essential oil, whereas the leaf essential oil of S. abortivum was dominated by (E)-caryophyllene (19.56%), δ -cadinene (11.03%), germacrene D (10.34%), and γ -muurolene (5.50%). It noted that both studied oil samples with the MIC/IC50 values of 8-32 µg/mL/4.56-10.37 µg/mL were comparable to the standard drugs in antimicrobial experiments against the Gram-positive bacteria Bacillus cereus and Enterococcus faecalis, and yeast Candida albicans. Molecular docking results showed that the main compound (E)-caryophyllene primarily formed hydrophobic interactions with the microbial proteins C. albicans N-myristoyl transferase B. cereus patB1, and E. faecalis carbamate kinase with the binding affinities of −6.969, −6.342, and −5.530 kcal/mol, respectively Conclusion: It is advised to isolate the main chemicals and conduct in vivo antibacterial experiments for both essential oils and their main compounds. [ABSTRACT FROM AUTHOR]

Traditional antifouling coatings for metal substrates typically involve three layers including an anticorrosion primer, a midcoat, and an antifouling paint. However, the limited bonding capacity between these layers restricts their effectiveness in industrial metal corrosion protection. In this work, we developed a single coating by dipping method on steel substrate that combines the anticorrosion properties of zinc and the antifouling properties of copper, using an ethyl silicate binder. This pigment mixture, containing flake ZnAl (5 wt%) and Cu2O (10 wt%) with varying spherical Zn content (30, 40, and 50 wt%), was created and tested for its anticorrosion capabilities. Electrical properties were characterized using electrochemical impedance spectroscopy and the polarization curve method. Results showed that after 60 days of immersion in 3.5 wt% NaCl solution, the low-frequency impedance modulus of the coatings increased with higher Zn content, with the 40 wt% Zn content achieving the highest efficiency, showing an impedance modulus value of 56.43 kΩ cm2. Stability evaluations revealed an increased release of Zn and Cu content in samples with higher Zn content. Antifouling assessments in natural seawater demonstrated that the Zn40 integrated coating had the lowest fouling density among the tested samples, with hard fouling surface coverage (FR ≥ 40) at 9.31% after three months. These findings highlight the effectiveness of the integrated coating utilizing Zn and Cu in providing robust corrosion protection, preventing settlement, and inhibiting fouling marine growth. [ABSTRACT FROM AUTHOR]

The synthesis and spectroscopic data of (E)-2-{4-[3-(thiophen-3-yl)acryloyl]phenoxy}acetic acid are described. Crystallization from an ethanol–water mixture resulted in the title compound, C30H23KO8S2 or [K(C15H11O4S)(C15H12O4S)]n, containing one molecule of the acid and one molecule of the potassium salt in the asymmetric unit. Both molecules share the H atom between their carboxyl groups and a potassium ion. The C=C bonds display an E configuration. The thiophene and phenyl rings in the two molecules are inclined by 43.3 (2) and 22.7 (2)°. The potassium ion is octahedrally coordinated by six O atoms. This distorted octahedron shares on opposite sides two oxygen atoms with inversion-related octahedra, resulting in chains of octahedra running in the [010] direction, which form ladder-like chains by C—H...π interactions. A Hirshfeld surface analysis indicates that the highest contributions to the surface contacts arise from interactions in which H atoms are involved, with the most important contribution being from H...H (31.6 and 31.9% for the two molecules) interactions.

The content of this paper focuses/shed light on the effects of X (X = S in P1 and X = O in P2) in C11H7NSX and R (R = H in P3, R = OCH3 in P4, and R = Cl in P5) in C18H9ON2S2-R on structural features and band gaps of the polythiophenes containing benzo[d]thiazole and benzo[d]oxazole by the Density Function Theory (DFT) method/calculation. The structural features including the electronic structure lattice constant (a), shape, total energy (Etot) per cell, and link length (r), are measured via band gap (Eg) prediction with the package of country density (PDOS) and total country density (DOS) of material studio software. The results obtained showed that the link angle and the link length between atoms were not changed significantly while the Etot was decreased from Etot = – 1904 eV (in P1) to Etot = – 2548 eV (in P2) when replacing O with S; and the Etot of P3 was decreased from Etot = – 3348 eV (in P3) when replacing OCH3, Cl on H of P3 corresponding to Etot = – 3575 eV (P4), – 4264 eV (P5). Similarly, when replacing O in P1 with – S to form P2, the Eg of P1 was dropped from Eg = 0.621 eV to Eg = 0.239 eV for P2. The Eg of P3, P4, and P5 is Eg = 0.006 eV, 0.064 eV, and 0.0645 eV, respectively. When a benzo[d]thiazole was added in P1 (changing into P3), the Eg was extremely strongly decreased, nearly 100 times (from Eg = 0.621 eV to Eg = 0.006 eV). The obtained results serve as a basis for future experimental work and used to fabricate smart electronic device.

Objectives: The genus Glochidion (the family Phyllanthaceae) is used for various medicinal purposes, such as dysentery, diarrhea, cough, and skin protection. A review of phytochemical and pharmacological aspects for this remains unavailable. The current study tends to sum up a detailed list of phytochemicals, and their role in biological examinations. Methods: References in English were obtained by an extensive search across various electronic data sources, encompassing Web of Science, PubMed, Google Scholar, and Science Direct. The "Sci-Finder" was also utilized to find references and revise chemical structures. Referenced documents have been gathered from the 1960s to date. It also noted that Glochidion, phytochemistry, and pharmacology are likely the keywords to seek for references. Results: Over 240 naturally occurring phytochemicals were isolated and identified from various Glochidion tissues, including terpenoids, sterols, saponins, lignans, flavonoids, mono -phenols, megastigmanes, butenolides, glycosides, alkaloids, cyanogens, tocopherols, fatty acids, and others. Three naturally occurring triterpenoids glochidonol, glochidiol, and glochidone are the likely characteristic metabolites, being isolated frequently. Glochidion crude extracts and their isolated compounds have been demonstrated as potential agents in various pharmacological targets, such as cytotoxicity, antioxidant, antiinflammation, and neuron and liver protection. Conclusion: Several isolates acted as promising agents in pharmacological assays. The anticancer mechanisms of various triterpenoids and saponins, especially new and potential compounds, are expected. Pharmacological advancements to enhance the efficacies of Glochidion constituents, such as synergistic combinations and nano-drug formulations, are encouraged. [ABSTRACT FROM AUTHOR]

The synthesis, spectroscopic data, crystal and molecular structures of two N′-(1-phenylbenzylidene)-2-(thiophen-3-yl)acetohydrazides, namely N′-[1-(4-hydroxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C13H10N2O2S, (3a), and N′-[1-(4-methoxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C14H14N2O2S, (3b), are described. Both compounds differ in the substituent at the para position of the phenyl ring: –OH for (3a) and –OCH3 for (3b). In (3a), the thiophene ring is disordered over two orientations with occupancies of 0.762 (3) and 0.238 (3). The configuration about the C=N bond is E. The thiophene and phenyl rings are inclined by 84.0 (3) and 87.0 (9)° for the major- and minor-occupancy disorder components in (3a), and by 85.89 (12)° in (3b). Although these dihedral angles are similar, the conformation of the linker between the two rings is different [the C—C—C—N torsion angle is −ac for (3a) and −sc for (3b), while the C6—C7—N9—N10 torsion angle is +ap for (3a) and −sp for (3b)]. A common feature in the crystal packing of (3a) and (3b) is the presence of N—H...O hydrogen bonds, resulting in the formation of chains of molecules running along the b-axis direction in the case of (3a), or inversion dimers for (3b). The most prominent contributions to the surface contacts are those in which H atoms are involved, as confirmed by an analysis of the Hirshfeld surface.

Background: Obstructive sleep apnea (OSA) is a common disorder and can lead to many severe complications; however, the majority of patients remain undiagnosed. Although polysomnography (PSG) remains the gold standard of diagnosis, it is usually uncomfortable and costly for patients. Purpose: The study aims to assess the agreement of the AHI measured by polygraphy (PG) (Philips Alice NightOne) with that of polysomnography (Philips Alice PDx) simultaneously recorded in-lab. Methods: A total of 11 voluntary participants over 18 years old underwent one night of simultaneous PSG and PG recording in sleep laboratories. Studied parameters (AHI, OAI, CAI, MAI, and minSpO2) were analyzed and reported by the Philips Sleepware G3 software. PSG and PG results were scored by qualified staff. Results: In terms of AHI, the mean AHI derived from PG was different from that of PSG—7.78 and 2.37 events/h, respectively. A Bland–Altman analysis of the AHI on PSG versus PG showed a mean difference of 5.41; limits of agreement (equal to ±2 standard deviations) were from −6.74 to 17.56. The Bland–Altman analysis showed a slight difference between the two methods, with a mean difference of −0.12 events/h in CAI, 1.35 events/h in OAI, and 0.42 events/h in MAI. Conclusions: In the population with a low suspicion of OSA, the PG showed a low agreement with the simultaneous PSG in the sleep lab. Therefore, PG should only be used as a screening method. Further studies with sufficient sensors in the expanded populations of OSA are needed.

In the title compound, C13H11N3S2, the phenyl ring is twisted from the 1,2,4-triazole plane by 63.35 (9)° and by 47.35 (9)° from the thiophene plane. In the crystal, chains of molecules running along the c-axis direction are formed by N—H...S interactions [graph-set motif C(4)]. The 1,2,4-triazole and phenyl rings are involved in π–π stacking interactions [centroid–centroid distance = 3.4553 (10) Å]. The thiophene ring is involved in C—H...S and C—H...π interactions. The intermolecular interactions in the crystal packing were further analysed using Hirshfield surface analysis, which indicates that the most significant contacts are H...H (35.8%), followed by S...H/H...S (26.7%) and C...H/H...C (18.2%).

Phytochemical study of green propolis alcohol extract of Brazilian Caatinga Mimosa tenuiflora (Willd.) Poir resulted in the separation of six flavonoids, including quercetin 3‐methyl ether (1) and 3,3′‐O‐dimethylquercetin (2), and four flavanones eriodictyol 5‐O‐methyl ether (3), 5,4′‐dihydroxy‐6,7‐dimethoxyflavanone (4), licoflavanone (5), and macarangaflavanone B (6). All these metabolites were first isolated from green propolis and the genus Mimosa. Metabolites 3–4 also established chemotaxonomic significance since they had never been observed in the bean family Fabaceae. Flavones 1–2 showed strong antioxidative activity against DPPH (1,1‐diphenyl‐2‐picryl hydrazyl) radicals with IC50 values of 12.40 and 16.23 μg/mL, respectively. All six isolates showed anti‐inflammatory effects against NO (nitric oxide) production in LPS (lipopolysaccharide)‐stimulated Raw 264.7 cells, in which the activity of flavone 1 was better than the standard dexamethasone (IC50 13.35 μg/mL). Flavonoids 1–3 also strongly controlled the growth of the Gram‐positive bacteria Bacillus subtilis ATCC 6051, and Staphylococcus aureus ATCC 29213 with MIC values of 32–64 μg/mL. Six isolated flavonoids exhibited strong or moderate mosquito larvicidal activity against Aedes aegypti and Ae. albopictus fourth instar larvae with the 24 h LC50 values of 29.62–55.89 μg/mL. By in silico approach, compound 1 was a non‐toxic agent with an LD50 value of 5000 mg/kg. [ABSTRACT FROM AUTHOR]

The title compound, C11H7NS2, was prepared in high yield (87%) using a solvent-free microwave-assisted synthesis. The structure shows whole-molecule disorder with occupancies for two orientations (A and B) of 0.4884 (10) and 0.5116 (10), respectively. The thiophene and benzothiazole rings are almost planar and make dihedral angles of 10.02 (18) and 12.54 (19)° for orientations A and B, respectively. Slipped π–π stacking between the aromatic rings, together with C—H...π, C—H...S and C—H...N interactions, result in a herringbone motif in the crystal packing.

In the title compound, C7H8N4S2, the thiophene ring shows rotational disorder over two orientations in a 0.6957 (15):0.3043 (15) ratio. The plane of the 1,2,4-triazole ring makes a dihedral angle of 75.02 (17)° with the major-disorder component of the thiophene ring. In the crystal, two types of inversion dimers, described by the graph-set motifs R22(8) and R22(10), are formed by N—H...S interactions. Chains of molecules running in the [101] direction are linked by weaker N—H...N interactions. The thiophene ring is involved in π–π and C—H...π interactions.

The title compound, C9H8N2O2S3, crystallizes with two molecules (A and B) in the asymmetric unit. Both have similar conformations (overlay r.m.s. deviation = 0.209 Å) and are linked by an N—H...O hydrogen bond. In both molecules, the thiophene rings show orientational disorder, with occupancy factors of 0.6727 (17) and 0.3273 (17) for molecule A, and 0.7916 (19) and 0.2084 (19) for molecule B. The five-membered rings make an angle of 79.7 (2)° in molecule A and an angle of 66.8 (2)° in molecule B. In the crystal, chains of molecules running along the a-axis direction are linked by N—H...O hydrogen bonds. The interaction of adjacent chains through N—H...O hydrogen bonds leads to two types of ring structures containing four molecules and described by the graph-set motifs R44(18) and R42(14).