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Over the past decades, 2(5H)-furanone derivatives have been extensively studied because of their promising ability to prevent the biofilm formation by various pathogenic bacteria. Here, we report the synthesis of a series of optically active sulfur-containing 2(5H)-furanone derivatives and characterize their biological activity. Novel thioethers were obtained by an interaction of stereochemically pure 5-(l)-menthyloxy- or 5-(l)-bornyloxy-2(5H)-furanones with aromatic thiols under basic conditions. Subsequent thioethers oxidation by an excess of hydrogen peroxide in acetic acid resulted in the formation of the corresponding chiral 2(5H)-furanone sulfones. The structure of synthesized compounds was confirmed by IR and NMR spectroscopy, HRMS, and single crystal X-ray diffraction. The leading compound, 26, possessing the sulfonyl group and l-borneol moiety, exhibited the prominent activity against Staphylococcus aureus and Bacillus subtilis with MICs of 8 μg/mL. Furthermore, at concentrations of 0.4–0.5 μg/mL, the sulfone 26 increased two-fold the efficacy of aminoglycosides gentamicin and amikacin against S. aureus. The treatment of the model-infected skin wound in the rat with a combination of gentamicin and sulfone 26 speeded up the bacterial decontamination and improved the healing of the wound. The presented results provide valuable new insights into the chemistry of 2(5H)-furanone derivatives and associated biological activities.

The crystal structure and chemical composition of a crystal of Mg-bearing phase Egg with a general formula M1-x3+Mx2+SiO4H1+x (M3+=Al, Cr; M2+=Mg, Fe), where x=35, produced by subsolidus reaction at 24 GPa and 1400°C of components of subducted oceanic slabs (peridotite, basalt, and sediment), was analyzed by electron microprobe and single-crystal X-ray diffraction. Neglecting the enlarged unit cell and the consequent expansion of the coordination polyhedra (as expected for Mg substitution for Al), the compound was found to be topologically identical to phase Egg, AlSiO3OH, space group P21/n, with lattice parameters a=7.2681(8), b=4.3723(5), c=7.1229(7) Å, β=99.123(8)°, V=223.49(4) Å3, and Z=4. Bond-valence considerations lead to hypothesize the presence of hydroxyl groups only, thereby excluding the presence of the molecular water that would be present in the hypothetical end-member MgSiO3·H2O. We thus demonstrate that phase Egg, considered as one of the main players in the water cycle of the mantle, can incorporate large amounts of Mg in its structure and that there exists a solid solution with a new hypothetical MgSiH2O4 end-member, according to the substitution Al3+⇌Mg2++H+. The new hypothetical MgSiH2O4 end-member would be a polymorph of phase H, a leading candidate for delivering significant water into the deepest part of the lower mantle.

Trichloro niobium(V) complexes 3 and 4 with the sulfur- or selenium-bridged [OEO]-type bis(phenolate) ligands (E = S, Se) were synthesized and fully characterized on the basis of their NMR spectroscopic data and X-ray crystallographic analysis. In the crystalline state of 4, the [OSeO]-core of the ligand was coordinated to the niobium center in a fac-fashion. The corresponding tribenzyl niobium(V) complexes 5 and 6 were also prepared by the reactions of 3 and 4 with 3 equivalents of PhCH2MgCl in toluene. The X-ray diffraction analysis of 6 revealed that the distorted six-coordinated niobium center incorporated in the [OSeO]-type ligand took a mer-fashion, and one benzyl ligand was coordinated to the niobium center by η2-fashion. Complexes 5 and 6 were tested for the phenylacetylene polymerization that produced poly(phenylacetylene)s (PPAs), oligomers, and triphenylbenzenes (TPBs) depending on the chalcogen atom in the [OEO]-type ligand.

This study reports the fabrication and performance of single‐crystal organic field‐effect transistors (SC‐OFETs) based on three 5,15‐bisaryl‐tetrabenzoporphyrin (BP) derivatives: C8Ph‐BP, C8Ph‐Ph‐BP, and Ph‐BP, where C8Ph and Ph are 4‐n‐octylphenyl and phenyl groups, respectively. These compounds are designed to investigate how meso‐substituted C8Ph and Ph groups affect molecular packing and charge transport properties of BP derivatives. X‐ray crystallography analysis confirms that all derivatives exhibit a herringbone packing structure. SC‐OFETs using single crystals of each derivative demonstrate maximum hole mobilities of 1.64 cm2 V−¹ s−¹ for C8Ph‐BP, 0.89 cm2 V−¹ s−¹ for C8Ph‐Ph‐BP, and 1.21 cm2 V−¹ s−¹ for Ph‐BP. The high mobility of C8Ph‐BP is attributed to its interdigitated parallel π‐stacking, enhanced by van der Waals interactions between n‐octyl groups. In contrast, Ph‐BP and C8Ph‐Ph‐BP show lower charge mobilities. This work demonstrates the influence of the n‐octyl and meso‐phenyl groups on the packing arrangements and the charge transport efficiency in SC‐OFETs, offering insights into optimizing organic semiconductors for high‐performance electronic applications. This study explores single‐crystal organic field‐effect transistors (SC‐OFETs) based on 5,15‐bisaryl‐tetrabenzoporphyrin derivatives. It highlights the impact of meso‐substituted groups on molecular packing and charge transport. Among the derivatives, C8Ph‐BP achieves the highest hole mobility (1.64 cm2 V−¹ s−¹) due to enhanced π‐stacking with interdigitated layer‐by‐layer structure, offering valuable insights into optimizing organic semiconductors for high‐performance electronics.

The frontal megathrust of the Nankai Trough subduction zone is recognized as a seismogenic fault based on a record of frictional heating, but the underlying micromechanical processes that act on the fault surface are poorly known. Here we present a layer of fault gouge ∼2 mm thick within a core drilled across the megathrust, in which smectite‐rich siltstone has been transformed into a preferentially oriented illite aggregate. The nearly complete breakdown of smectite is consistent with fast frictional heating on this fault; however, the microtextures of the gouge and its surroundings are asserted one produced experimentally by slow slip. We suggest that slow slip with small shear strain has overprinted the textures produced by the previous faster and larger slip. This interpretation based on microtectonic evidence suggests a slow slip around the frontal megathrust took place during slow down, afterslip, or interseismic as observed now going in subduction zone. We suggest that the illite‐dominated gouge is conditionally stable, likely to shift from rapid to slow slip at different times. Plain Language Summary Recent dense seismic observations have revealed that both fast and slow earthquakes occur in the Nankai Trough megathrust, but the micro‐processes on the fault surface have not yet been clarified. In this study, we performed three‐dimensional structural analysis, electron microscopy observation, and microdomain X‐ray mineral analysis of the Nankai Trough frontal megathrust sample, which are presumed to be the earthquake generating fault. The results show that smectite is lost due to high velocity slip, and a composite planar fabric with relatively slow and small deformation is observed to override the fast deformation. Our observations suggest that the fault may experience both of fast and slow slip at different times. Key Points Microscopic and mineral analysis were performed on the Nankai Trough frontal megathrust sample collected by drilling The development of the Y‐P‐R1 fabric was observed, along with traces of fast deformation accompanied by the disappearance of smectite Two types of deformations registered in the gouge suggest rapid to slow slip at different times on the same fault

The comparative study of the crystal structure and structural features of thermally sublimed films with lead phthalocyanines with chlorine substituents at peripheral (PbPcCl 4 -p) and non-peripheral positions of the phthalocyanine ring (PbPcCl 4 -np) is reported. It is shown that as for non-substituted phthalocyanine lead, in PbPcCl 4 -p and PbPcCl 4 -np molecules, the lead cation is out of the plane of the macrocycle. PbPcCl 4 -p crystallizes in the tetragonal crystal system (space group I 4/ m ), and the PbPcCl 4 -p molecules are packed into vertical stacks along axis 4. The introduction of chlorine substituents into non-peripheral positions of the phthalocyanine ring causes a change in the crystal structure. PbPcCl 4 -np crystallizes in the space group P 2 1 / n , with PbPcCl 4 -np molecules being packed in layers along the b axis; inside one layer - in chains with alternating up and down orientations of lead atoms. The effect of the position of chlorine substituents on the microstructural features of PbPcСl 4 -p and PbPcCl 4 -np films is studied by powder X-ray diffraction and electronic absorption spectroscopy.

Calcium chelidonate [Ca(ChA)(H2O)3]n was obtained by semi-synthesis using natural chelidonic acid. The structure of the molecular complex was determined by X-ray diffraction analysis. The asymmetric unit of [Ca(ChA)(H2O)3]n includes chelidonic acid coordinated through three oxygen atoms, and three water ligands. The oxygen atoms of acid and oxygen atoms of water from each asymmetric unit are also coordinated to the calcium of another one, forming an infinite linear complex. Calcium geometry is close to the trigonal dodecahedron (D2d). The intra-complex hydrogen bonds additionally stabilize the linear species, which are parallel to the axis. In turn the linear species are packed into the 3D structure through mutual intercomplex hydrogen bonds. The osteogenic activity of the semi-synthetic CaChA was studied in vitro on 21-day hAMMSC culture and in vivo in mice using ectopic (subcutaneous) implantation of CaP-coated Ti plates saturated in vitro with syngeneic bone marrow. The enhanced extracellular matrix ECM mineralization in vitro and ectopic bone tissue formation in situ occurred while a water solution of calcium chelidonate at a dose of 10 mg/kg was used. The test substance promotes human adipose-derived multipotent mesenchymal stromal/stem cells (hAMMSCs), as well as mouse MSCs to differentiate into osteoblasts in vitro and in vivo, respectively. Calcium chelidonate is non-toxic and can stimulate osteoinductive processes.

Currently, the study of the scattering of ultrashort X-ray pulses (USPs) by various objects is an urgent task, in connection with the creation of powerful sources of USP generation. In this paper, the theory of the scattering of attosecond pulses by polyatomic structures is developed taking into account the magnetic component of USPs. It is shown that the scattering spectra depend not only on the structure of the target, but also on other characteristics of USPs. Results are presented of the calculation of the scattering spectra on various nanosystems, such as rings, groups of rings, carbon nanotubes (CNTs), and groups of co-directed CNTs (forest CNTs). The calculation results are presented in an analytical form, which allows a general analysis of the expressions. It was found that taking the magnetic component of the momentum into the scattering spectra into account leads to the generation of the second harmonic. In this case, the spectra have characteristic features and differ from the scattering spectra at the carrier frequency, which can complement ultra-high-resolution X-ray analysis. It is shown that the scattering spectra of some structures, for example, forest CNTs, have a strictly specified radiation direction and such material in the field of such USPs is non-reflective (completely black).

The utilization of solid fuels remains a significant contributor to air pollution, with well-documented adverse health consequences. In rural regions, the prevalence of solid fuel use for heating and cooking plays a pivotal role in shaping local air quality. This study focuses on evaluating personal exposure to gaseous pollutants originating from restaurants situated in Karunya Nagar, Coimbatore, Tamil Nadu, India. The study design considers establishments that use distinct energy sources, with a particular emphasis on those employing wood and liquefied petroleum gas. We measure the concentration of various pollutants, including particulate matter (PM1, PM2.5, PM10), carbon dioxide, formaldehyde, and total volatile organic carbon, utilizing advanced sensor technology. The levels of these pollutants are influenced by various factors, such as ventilation, chimney placement, stove type, fuel selection, time of exposure, frequency of exposure, and toxicity. Notably, our findings reveal that restaurants using wood as a cooking fuel tend to release higher quantities of gaseous pollutants compared to those employing liquefied petroleum gas. In addition to quantitative measurements, we employ comprehensive chemical characterization techniques, including scanning electron microscopy, X-ray diffraction analysis, energy dispersive X-ray analysis, and Fourier transform infrared spectroscopy, to delineate the morphology, chemical composition, and other essential properties of the emitted particulate matter. Our study sheds light on the potential health repercussions faced by rural residents who heavily rely on solid domestic fuels. The insights derived from this research not only contribute to the reduction of air pollution exposure but also facilitate the development of exposure assessment models for forthcoming epidemiological investigations. This aligns with the broader objectives of Sustainable Development Goals and seeks to enhance the well-being of women in rural Southern India.

Crystal chemical algorithms were used to estimate the chemical composition of selected mineral phases observed with the CheMin X-ray diffractometer onboard the NASA Curiosity rover in Gale crater, Mars. The sampled materials include two wind-blown soils, Rocknest and Gobabeb, six mudstones in the Yellowknife Bay formation (John Klein and Cumberland) and the Murray formation (Confidence Hills, Mojave2, and Telegraph Peak), as well as five sandstones, Windjana and the samples of the unaltered Stimson formation (Big Sky and Okoruso) and the altered Stimson formation (Greenhorn and Lubango). The major mineral phases observed with the CheMin instrument in the Gale crater include plagioclase, sanidine, P21/c and C2/c clinopyroxene, orthopyroxene, olivine, spinel, and alunite-jarosite group minerals. The plagioclase analyzed with CheMin has an overall estimated average of An40(11) with a range of An30(8) to An63(6). The soil samples, Rocknest and Gobabeb, have an average of An56(8) while the Murray, Yellowknife Bay, unaltered Stimson, and altered Stimson formations have averages of An38(2), An37(5), An45(7), and An35(6), respectively. Alkali feldspar, specifically sanidine, average composition is Or74(17) with fully disordered Al/Si. Sanidine is most abundant in the Wind-jana sample (∼26 wt% of the crystalline material) and is fully disordered with a composition of Or87(5). The P21/c clinopyroxene pigeonite observed in Gale crater has a broad compositional range {[Mg0.95(12)-1.54(17)Fe0.18(17)-1.03(9)Ca0.00-0.28(6)]Σ2Si2O6} with an overall average of Mg1.18(19)Fe0.72(7)Ca0.10(9)Si2O6. The soils have the lowest Mg and highest Fe compositions [Mg0.95(5)Fe1.02(7)Ca0.03(4)Si2O6] of all of the Gale samples. Of the remaining samples, those of the Stimson formation exhibit the highest Mg and lowest Fe [average = Mg1.45(7)Fe0.35(13)Ca0.19(6)Si2O6]. Augite, C2/c clinopyroxene, is detected in just three samples, the soil samples [average = Mg0.92(5)Ca0.72(2)Fe0.36(5)Si2O6] and Windjana (Mg1.03(7)Ca0.75(4)Fe0.21(9)Si2O6). Orthopyroxene was not detected in the soil samples and has an overall average composition of Mg0.79(6)Fe1.20(6)Ca0.01(2)Si2O6 and a range of [Mg0.69(7)-0.86(20)Fe1.14(20)-1.31(7)Ca0.00-0.04(4)]Σ2Si2O6, with Big Sky exhibiting the lowest Mg content [Mg0.69(7)Fe1.31(7)Si2O6] and Okoruso exhibiting the highest [Mg0.86(20)Fe1.14(20)Si2O6]. Appreciable olivine was observed in only three of the Gale crater samples, the soils and Windjana. Assuming no Mn or Ca, the olivine has an average composition of Mg1.19(12)Fe0.81(12)SiO4 with a range of 1.08(3) to 1.45(7) Mg apfu. The soil samples [average = Mg1.11(4)Fe0.89SiO4] are significantly less magnesian than Windjana [Mg1.35(7)Fe0.65(7)SiO4]. We assume magnetite (Fe3O4) is cation-deficient (Fe3-x∎xO4) in Gale crater samples [average = Fe2.83(5)∎0.14O4; range 2.75(5) to 2.90(5) Fe apfu], but we also report other plausible cation substitutions such as Al, Mg, and Cr that would yield equivalent unit-cell parameters. Assuming cation-deficient magnetite, the Murray formation [average = Fe2.77(2)∎0.23O4] is noticeably more cation-deficient than the other Gale samples analyzed by CheMin. Note that despite the presence of Ti-rich magnetite in martian meteorites, the unit-cell parameters of Gale magnetite do not permit significant Ti substitution. Abundant jarosite is found in only one sample, Mojave2; its estimated composition is (K0.51(12)Na0.49)(Fe2.68(7)Al0.32)(SO4)2(OH)6. In addition to providing composition and abundances of the crystalline phases, we calculate the lower limit of the abundance of X-ray amorphous material and the composition thereof for each of the samples analyzed with CheMin. Each of the CheMin samples had a significant proportion of amorphous SiO2, except Windjana that has 3.6 wt% SiO2. Excluding Windjana, the amorphous materials have an SiO2 range of 24.1 to 75.9 wt% and an average of 47.6 wt%. Windjana has the highest FeOT (total Fe content calculated as FeO) at 43.1 wt%, but most of the CheMin samples also contain appreciable Fe, with an average of 16.8 wt%. With the exception of the altered Stimson formation samples, Greenhorn and Lubango, the majority of the observed SO3 is concentrated in the amorphous component (average = 11.6 wt%). Furthermore, we provide average amorphous-component compositions for the soils and the Mount Sharp group formations, as well as the limiting element for each CheMin sample.