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By using spectroscopic techniques, the 3,5-diethyl-2r,6c-diarylpiperidin-4-one oxime picrates (DDPPOP and DDMPPOP) were characterised by elemental analysis, FT-IR, 1H, 13C and 2D NMR and mass spectral techniques. The compounds follow a normal chair conformation with all substituents orientated equatorially, as indicated by the reported chemical shifts and coupling constants from the NMR spectral data. The optimised molecular structures of the title compounds were done by using DFT method with B3LYP/6-311++G(d,p) theory. According to the calculated first hyperpolarizability (β0) values of the compounds display non-linear optical (NLO) behaviour. The molecule may have undergone intra-molecular charge transfer, according to the HOMO–LUMO transition. The reactive sites of the title molecule was analysed by using the Molecular Electrostatic Potential (MEP) surface. The Mulliken atomic charges were calculated by using same basis set. The antibacterial and antifungal activity of the title compounds was examined by biological study. Docking studies were thoroughly conducted to establish knowledge regarding the molecular interactions between protein and this compound. This study is further developed and uses the idea of graph colouring in mathematical computation to support the molecular structure we created using NMR spectroscopy. [ABSTRACT FROM AUTHOR]

In this paper, various substituted 3t-pentyl-2r,6c-diarylpiperidin-4-one oxime picrates were synthesised and characterised by elemental analysis, FT-IR, NMR, UV–Visible and Fluorescence spectral techniques. For compound 1, NMR spectral assignments were made unambiguously by their one-dimensional (1H and 13C NMR) and two-dimensional (1H–1H COSY, NOESY, HSQC and HMBC) spectra. The observed chemical shifts and coupling constants suggest that compounds 1–7 adopt normal chair conformation with the equatorial orientation of all the substituents like aryl group at C(2) and C(6) and pentyl group at C(3). Compounds 2 and 7 exhibited potent anti-bacterial activity and fungal activity against all the tested strains while all the other compounds showed moderate activity. The molecular structure of compounds (1–7) was optimised at the density functional theory (DFT)/B3LYP/6-311++G(d,p) level of basis set. The calculated first hyperpolarisability (β0) values show that all the molecules might have non-linear optical (NLO) behaviour. The HOMO–LUMO transition implies that intra-molecular charge transfer takes place within the molecule. The molecular electrostatic potential (MEP) surface is used to understand the reactive sites of a molecule. [ABSTRACT FROM AUTHOR]

A wearable glove-based sensor is a portable and practical approach for onsite detection/monitoring of a variety of chemical threats. Herein, we report a flexible and sensitive wearable sensor fabricated on the nitrile glove fingertips by stencil-printing technique. The working electrodes were modified with multiwalled carbon nanotubes (MWCNTs)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) for sensitive and real-time analyses of hazardous or chemical treats, as picric acid (PA) explosive, diazepam (DZ) as drug-facilitated crimes and the emerging pollutant 4-nitrophenol (4-NP). The multi-sensing platform towards PA, 4-NP, and DZ offers the ability of in-situ qualitative and quantitative analyses of powder and liquid samples. A simple sampling by touching or swiping the fingertip sensor on the sample or surface under investigation using an ionic hydrogel combined with fast voltammetry measurement provides timely point-of-need analyses. The wearable glove-based sensor uses the square wave voltammetry (SWV) technique and exhibited excellent performance to detect PA, 4-NP, and DZ, resulting in limits of detection (LOD) of 0.24 μM, 0.35 μM, 0.06 μM, respectively, in a wide concentration range (from 0.5 μM to 100 μM). Also, we obtained excellent manufacturing reproducibility with relative standard deviations (RSD) in the range of 3.65%-4.61% using 7 different wearable devices (n = 7) and stability in the range of 4.86%-6.61% using different electrodes stored for 10 days at room temperature (n = 10), demonstrating the excellent sensor-to-sensor reproducibility and stability for reliable in-field measurements. The stretchable sensor presented great mechanical robustness, supporting up to 80 bending or stretching deformation cycles without significant voltammetric changes. Collectively, our wearable glove-based sensor may be employed for analyses of chemical contaminants of concern, such as explosives (PA), drugs (DZ), and emerging pollutants (4-NP), helping in environmental and public safety control., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Four new polyketides, namely furantides A-B ( 1 - 2 ), talamin E ( 3 ) and arugosinacid A ( 4 ), and two known polyketides were obtained from the mangrove-derived fungus Penicillium sp. HDN15-312 using the One Strain Many Compounds (OSMAC) strategy. Their chemical structures, including configurations, were elucidated by detailed analysis of extensive NMR spectra, HRESIMS and ECD. The DPPH radicals scavenging activity of 3 , with an IC 50 value of 6.79 µM, was better than vitamin C.

This study aimed to enhance the antioxidant activity of carboxymethyl inulin (CMI) by chemical modification. Therefore, a series of cationic Schiff bases bearing heteroatoms were synthesized and incorporated into CMI via ion exchange reactions, ultimately preparing 10 novel CMI derivatives (CMID). Their structures were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. The radical scavenging activities and reducing power of inulin, CMI, and CMID were studied. The results revealed a significant enhancement in antioxidant activity upon the introduction of cationic Schiff bases into CMI. Compared to commercially available antioxidant Vc, CMID demonstrated a broader range of antioxidant activities across the four antioxidant systems analyzed in this research. In particular, CMID containing quinoline (6QSCMI) exhibited the strongest hydroxyl radical scavenging activity, with a scavenging rate of 93.60 % at 1.6 mg mL -1 . The CMID bearing imidazole (2MSCMI) was able to scavenge 100 % of the DPPH radical at 1.60 mg mL -1 . Furthermore, cytotoxicity experiments showed that the products had good biocompatibility. These results are helpful for evaluating the feasibility of exploiting these products in the food, biomedical, and cosmetics industries., Competing Interests: Declaration of competing interest The authors have declared no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Fish-borne pathogens such as A. hydrophila and F. aquidurense are the most resistant strains in pisciculture farming. Removing the aforementioned pathogens without antibiotics presents a formidable challenge. To overcome this problem, silver nanoparticles (AgNPs) are synthesized using silver nitrate, water medium, and as an AzadirachtaIndica leaf extract via the green synthesis route. X-ray diffraction (XRD) pattern results authenticate the synthesized material is the face-centered cubic structure of silver. The optical absorption edge of the synthesized product was found at the wavelength of 440 nm from the UV-visible spectra, which is confirmed to relate to the Surface Plasmon Resonance peaks of silver particles. In addition, the optical band gap value of the synthesized Ag sample is measured to be 2.81 eV from the obtained optical absorption spectra. EDX spectrum of the synthesized product also supports confirming the silver particle formation. The FT-IR spectra of the neem extract and silver nanoparticles showed their characteristic functional groups, respectively. The presence of bands between 1000 cm -1 to 500 cm -1 indicates to the formation of silver particles. Spherical particles appeared in the synthesized Ag using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The particle size of Ag NPs was measured as 40 nm and 62 ± 10 nm by TEM and Dynamic Light Scattering (DLS). The zeta potential was also measured as -12 mV showing the synthesized sample's stable nature. Using the DPPH assay, synthesized AgNPs were taken along with the various concentrations of ascorbic acid (20, 40, 60, 80, and 100 μg/mL) to examine the free radical scavenging activity (RSA). RSA value is higher (84 ± 2 %) for synthesized AgNPs at higher concentration (100 μg/mL) than 21 ± 2 % at low concentration (100 μg/mL). The antimicrobial efficacy of the AgNPs against A. hydrophila and F. aquidurense was performed through the agar diffusion method and its results showed the inhibitory zones of the F.aquidurense and A. hydrophila were measured as 25 ± 3 mm, and 28 ± 4 mm respectively. The synthesized Ag particles showed excellent antimicrobial and antioxidant properties confirmed by antimicrobial and DPPH experiments. It implies that the green synthesized silver nanoparticles could be a good alternative for antibiotics in aquaculture farms. The exposure of low concentrations of silver nanoparticles to zebrafish and brine shrimp does not affect the viability and morphology. The exposure of silver nanoparticles in the fisheries in optimized concentration and time could control the fish-borne pathogens without antibiotics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interest or personal relationship that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate antioxidative features using 2,2-diphenyl-1-pycrylhydrazyl free radical (DPPH • ) scavenging method, bovine serum albumin (BSA)-binding properties with usage of spectrofluorimetric method, proliferative and cyto/genotoxic status by use of chromosome aberration test, and antimicrobial potential using broth microdilution method, followed by resazurin assay of benzyl-, isopropyl-, isobutyl and phenylparaben in vitro . Our results showed that all parabens had significant antiradical scavenger activity compared to p -hydroxybenzoic acid (PHBA) precursor. Higher mitotic index for benzyl-, isopropyl and isobutylparaben (250 µg/mL) in comparison with control was demonstrated. An increase in the frequency of acentric fragments in lymphocytes treated with benzylparaben and isopropylparaben (125 and 250 µg/mL), and isobutylparaben (250 µg/mL) was observed. Isobutylparaben (250 µg/mL) induced higher number of dicentric chromosomes. An increased number of minute fragments in lymphocytes exposed to benzylparaben (125 and 250 µg/mL) was found. A significant difference in the frequency of chromosome pulverization, between phenylparaben (250 µg/mL) and control, was detected. Benzylparaben (250 µg/mL) and phenylparaben (62.5 µg/mL) caused an increase in the number of apoptotic cells, while isopropylparaben (62.5, 125 and 250 µg/mL) and isobutylparaben (62.5 and 125 µg/mL) induced higher frequency of necrosis. Minimum inhibitory concentration (MIC) of tested parabens ranged 15.62-250 µg/mL for bacteria, and 125-500 µg/mL for the yeast. Minimum microbiocidal concentration ranged 31.25 to 500 µg/mL, and 250 to 1000 µg/mL in bacteria and fungi respectively. The lowest MICs for bacteria were observed for phenyl- (15.62 µg/mL) and isopropylparaben (31.25 µg/mL) against Enterococcus faecalis .

Microwave-assisted extraction of mucilage from juá was investigated using response surface methodology. The optimal conditions for extraction were a power of 300 W, an extraction time of 240 s, a pH of 8.0, and a water/sample ratio of 1/6, which achieved a 26.43% yield. The monosaccharide composition and antioxidant activity of the mucilage from juá fruits from different regions of Caatinga were investigated. The fruits from Agreste Paraibano showed the highest mucilage extraction yield (18.64%) compared to that of fruits from Mata Paraibana (MP) (12.37%), Borborema (BB) (11.47%), and Sertão Paraibano (8.31%) (p < 0.05). Glucose (32.8%-50.8%) and arabinose (19.3%-32.9%) were the main monosaccharides found in juá mucilage. The mucilage from fruits in the MP presented the highest antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl and oxygen radical absorbance capacity assays. Our results demonstrated the potential for the future exploration and application of juá mucilage in the food industry. PRACTICAL APPLICATION: Juá (Ziziphus joazeiro Mart.) mucilage contains phenolic compounds and antioxidant activity, and its extraction by MAE is efficient, as it contributed to a higher yield., (© 2024 Institute of Food Technologists.)

The relevance of the present work on the mixed ligand alkaline-earth metal picrates can be evidenced by the following statement from Fromm's review which is quoted verbatim " I While magnesium and calcium are the best studied among the alkaline earth metal compounds, the heavier alkaline earth metals have not yet been studied in detail, and recent results show the potential progress to be done i " [[1]]. A majority (10) of the compounds are discrete monomers which includes the single Mg-picrate and the picrates of Ca, while one Sr-picrate (entry no. 7) and three Ba picrates (entry no. 9, 13 and 14) are coordination polymers. Keywords: alkaline-earth metal; barium coordination polymer; calcium; nicotinamide; picrate; strontium EN alkaline-earth metal barium coordination polymer calcium nicotinamide picrate strontium 211 219 9 05/13/22 20220501 NES 220501 Dedicated to Professor Christian Näther on the occasion of his 60th birthday. In view of its special position, each Ba cation is bridged via a nic ligand to four symmetry related Ba cations and all Ba---Ba separations in the layer are identical. [Extracted from the article]

Abstract: A new cyclopentenone, 5-hydroxycyclopeni cillone (1), was isolated together with three known compounds, ar-turmerone (2), citreoisocoumarin (3), and 6-O-methyl-citreoisocoumarin (4), from a culture of the sponge-derived fungus Trichoderma sp. HPQJ-34. The structures of 1-4 were characterized using comprehensive spectroscopic analyses. The absolute configuration of 1 was determined by comparison of electronic circular dichroism (ECD) spectra with literature values used for the reported analogue, cyclopenicillone (5), which was not isolated in this research. Compound 1 was shown to scavenge 2,2-diphenyl-1-picrylhydrazyl free radicals, and decrease β-amyloid (Aβ) fibrillization in vitro. Moreover, 1 significantly reduced H₂O₂-induced neurotoxicity in SH-SY5Y cells. These findings suggested that compound 1, a newly discovered cyclopentenone, has moderate anti-oxidative, anti-Aβ fibrillization properties and neuroprotective effects, and might be a good free radical scavenger.

Adhesive mussel foot proteins (Mfps) rely in part on DOPA (3,4-dihydroxyphenyl-l-alanine) side chains to mediate attachment to mineral surfaces underwater. Oxidation of DOPA to Dopaquinone (Q) effectively abolishes the adsorption of Mfps to these surfaces. The thiol-rich mussel foot protein-6 (Mfp-6) rescues adhesion compromised by adventitious DOPA oxidation by reducing Q back to DOPA. The redox chemistry and kinetics of foot-extracted Mfp-6 were investigated by using a nonspecific chromogenic probe to equilibrate with the redox pool. Foot-extracted Mfp-6 has a reducing capacity of ~17 e(-) per protein; half of this comes from the cysteine residues, whereas the other half comes from other constituents, probably a cohort of four or five nonadhesive, redox-active DOPA residues in Mfp-6 with an anodic peak potential ~500 mV lower than that for oxidation of cysteine to cystine. At higher pH, DOPA redox reversibility is lost possibly due to Q scavenging by Cys thiolates. Analysis by one- and two-dimensional proton nuclear magnetic resonance identified a pronounced β-sheet structure with a hydrophobic core in foot-extracted Mfp-6 protein. The structure endows redox-active side chains in Mfp-6, i.e., cysteine and DOPA, with significant reducing power over a broad pH range, and this power is measurably diminished in recombinant Mfp-6.

The California mussel, Mytilus californianus, adheres in the highly oxidizing intertidal zone with a fibrous holdfast called the byssus using 3, 4-dihydroxyphenyl-l-alanine (DOPA)-containing adhesive proteins. DOPA is susceptible to oxidation in seawater and, upon oxidation, loses adhesion. Successful mussel adhesion thus depends critically on controlling oxidation and reduction. To explore how mussels regulate redox during their functional adhesive lifetime, we tracked extractable protein concentration, DOPA content and antioxidant activity in byssal plaques over time. In seawater, DOPA content and antioxidant activity in the byssus persisted much longer than expected-50% of extractable DOPA and 30% of extractable antioxidant activity remained after 20 days. Antioxidant activity was located at the plaque-substrate interface, demonstrating that antioxidant activity keeps DOPA reduced for durable and dynamic adhesion. We also correlated antioxidant activity to cysteine and DOPA side chains of mussel foot proteins (mfps), suggesting that mussels use both cysteine and DOPA redox reservoirs for controlling interfacial chemistry. These data are discussed in the context of the biomaterial structure and properties of the marine mussel byssus.

Background and Aim: Bombax buonopozense (Bombacaceae) leaves have been used traditionally for arthritis in south-western Nigeria. Therefore, the aim of the study was to investigate the antioxidant and anti-arthritic activity of B. buonopozense in Complete Freund adjuvant-induce arthritic wistar rats., Experimental Procedure: The plant leaves methanol extract and fractions were screened for preliminary phytochemicals and brine shrimp lethality was determined. Total phenolic content (TPC), Total flavonoid content (TFC) as well as anti-oxidant activity of the extract and fractions were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Cyclophosphamide, gallic acid, and ascorbic acid were used as standards respectively. Anti-arthritic activity of crude methanol extract (BBME) at 100, 200 and 400mg/kg was evaluated in complete Freund's adjuvant (CFA) induced arthritis model in rats. Data were analysed using Graph pad prism version 5, two-way and one-way ANOVA, and Bonferroni post hoc test., Results and Conclusion: Phytochemical screening revealed the presence of flavonoids, alkaloids, and phenolics. The brine shrimp lethality assay of the crude extract and fractions gave LC 50 value≥1000μg/mL, compared to Cyclophosphamide (LC 50 =224.7±0.35μg/mL). The BBME had TPC value of 19.8±0.56mg GAE/g, while the TFC of ethyl acetate fraction was the highest (173.5±0.05mg QE/g). The ethyl acetate fraction has the highest antioxidant activity (IC 50 =20.96±0.23μg/mL) as compared to ascorbic acid (2.8±0.01) and rutin (20.6±9.26μg/mL). BBME significantly reduced the paw circumference. BBME (400mg/kg) prevented biochemical changes to a greater extent than Celecoxib (20mg/kg). Bombax buonopozense leaves could be an effective antiarthritic and holds prospect in the treatment of rheumatoid arthritis., (Copyright © 2024 Académie Nationale de Pharmacie. All rights reserved.)

Objective: Satureja kermanica is a native species with a relatively wide distribution in Iran, which has been studied less. Due to the low stability of the plants, in this study, the methanolic extract of S. kermanica (MSK) along with a nanoemulsion (NEK) preparation was evaluated in terms of antioxidant and cytotoxic activity., Material and Methods: The aerial parts of S. kermanica were collected and after studying the organoleptic characteristics and quality control parameters, were extracted with methanol. Total phenolic compounds and total flavonoids of the plant were measured. A nanoemulsion preparation was prepared using ultrasonication method from S. kermanica extract. After measuring the particle size of nanoemulsion, both MSK and NEK were evaluated for their antioxidant and cytotoxic activity using DPPH scavenging assay and MTT colorimetric method on breast cancer cell line (MCF-7) respectively., Results: Phytochemical studies exhibited the presence of secondary metabolites including flavonoids, tannins, steroids and carbohydrates in the plant. Based on the histogram of the SBL nanosizer, the average diameter of nanoemulsion was determined as 37.09nm. Both MSK and NEK showed dose-dependent antioxidant and cytotoxic activity. The IC 50 value of MSK and NEK for DPPH inhibition was 30.105±2.781 58.14±0.84μg/mL and for toxicity toward MCF-7 cell line was 1251.088 and 201.745±4.554μg/mL respectively., Conclusion: MSK and NEK showed antioxidant and cytotoxic activity, but in NEK, the antioxidant and cytotoxic potential of the plant was more prominent, which may be due to the rapid release of the bioactive component from the nanoemulsion., (Copyright © 2024. Published by Elsevier Masson SAS.)

A dynamic chitosan-based ZnO nanocomposite (NC) was fabricated via a cost-effective formulation and an eco-friendly procedure utilizing Cissus quadrangularis (CQ) plant extract. This study investigates the antimicrobial and antioxidant properties, together with the cytocompatibility aspects of chitosan-incorporated ZnO nanocomposite (CS-ZnO/CQE). The formation and structural morphology of the nanocomposites were examined using FTIR, UV-Vis, XRD, XPS, BET, TGA, SEM, and TEM techniques. The antibacterial test results demonstrated the greatest inhibitory zone diameter against S. aureus (19 ± 1.00 mm) and E. coli (17 ± 1.05 mm), assessed through agar well diffusion method. Also, the composite exhibited a DPPH inhibition rate of 78.7 ± 0.34 %, indicating its high effectiveness in neutralizing free radicals. In addition, the nanocomposite exhibited less toxicity towards human erythrocytes, HDF and HEK-293 cells as a result of the biocompatibility exhibited by CS, ZnO, and CQ plant extract. Likewise, it has exceptional cell migratory capacity and possesses biodegradability factors. These observations strongly suggest the potential of CS-ZnO/CQE as a cutting-edge antibacterial and antioxidant agent to be implemented in the medical sector., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Distillers' grains are rich in protein and constitute a high-quality source of various bioactive peptides. The purpose of this study is to identify novel bioactive peptides with α-glucosidase inhibitory, antioxidant, and insulin resistance-ameliorating effects from distiller's grains protein hydrolysate. Three novel peptides (YPLPR, AFEPLR, and NDPF) showed good potential bioactivities, and the YPLPR peptide had the strongest bioactivities, whose IC 50 values towards α-glucosidase inhibition, radical scavenging rates of 2,2'-azino-bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were about 5.31 mmol/L, 6.05 mmol/L, and 7.94 mmol/L, respectively. The glucose consumption of HepG2 cells treated with YPLPR increased significantly under insulin resistance condition. Moreover, the YPLPR peptide also had a good scavenging effect on intracellular reactive oxygen species (ROS) induced by H 2 O 2 (the relative contents: 102.35% vs. 100%). Molecular docking results showed that these peptides could stably combine with α-glucosidase, ABTS, and DPPH free radicals, as well as related targets of the insulin signaling pathway through hydrogen bonding and van der Waals forces. This research presents a potentially valuable natural resource for reducing oxidative stress damage and regulating blood glucose in diabetes, thereby increasing the usage of distillers' grains peptides and boosting their economic worth.

Artemisia vestita Wall. Ex Besser is a folklore medicinal plant that belongs to Asteraceae family and a treasure trove of drugs. The aim of this research study was to investigate the phytoconstituents, antimicrobial activity, antioxidant, anti-inflammatory, cytotoxicity and wound healing potential of A. vestita leaf extract (ALE). Phytochemical analysis of the ALE was carried out by Soxhlet extraction and GCMS (gas chromatography-mass spectrometry) analysis. Antimicrobial activity was performed by the agar well diffusion method against selected bacterial and fungal strains. Free radical scavenging potential was evaluated by DPPH (2,2-Diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and FRAP (Ferric reducing antioxidant power) assays. Anti-inflammatory activity was performed by enzyme inhibition assay-COXII. The cytotoxicity of ALE on HaCaT cells was studied via MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. An in vitro scratch assay was performed for the evaluation of the wound healing property of ALE. It showed satisfactory antimicrobial activity against Staphylococcus aureus (14.2 ± 0.28 mm), Escherichia coli (17.6 ± 0.52 mm), Bacillus subtilis (13.1 ± 0.37 mm), Streptococcus pyogenes (17.3 ± 0.64 mm), Proteus mirabilis (9.4 ± 0.56 mm), Aspergillus niger (12.7 ± 0.53 mm), Aspergilus flavus (15.3 ± 0.25 mm) and Candida albicans (17.6 ± 0.11 mm). In ALE, 36 phytochemicals were detected by GCMS analysis, but 22 were dominant. Moreover, the ALE was effective in scavenging free radicals with different assays and exhibited reasonable anti-inflammatory activity. The MTT assay revealed that ALE had a cytotoxic effect on the HaCaT cells. The scratch assay showed 94.6% wound closure (after 24 h incubation) compared to the positive control Cipladine, which is remarkable wound healing activity. This is the first report on the wound healing property of A. vestita , which can serve as a potential agent for wound healing and extends knowledge on its therapeutic potential.

Demonstration of glycogen in tissue holds considerable diagnostic relevance across various pathological conditions, particularly in certain tumors. The histochemical staining of glycogen using methods utilizing Schiff's reagents is subject to influences arising from the type of fixative, fixation temperature, and oxidizing agents employed. This study aimed to assess diverse fixatives, fixation temperatures, and oxidizing agents, each with variable treatment durations, in conjunction with Schiff's reagent for optimal glycogen demonstration. Paraffin blocks derived from a rabbit's liver served as the experimental substrate, encompassing 340 paraffin sections subjected to different procedures. For tissues fixed at 4 °C, good staining outcomes, as determined by the periodic acid-Schiff (PAS) stain, were observed with 10% neutral buffered formalin (NBF), 80% alcohol, and Bouin's solution. Tissues fixed at room temperature (RT) demonstrated good PAS staining results with both 10% NBF and 80% alcohol. Notably, other oxidizing agents exhibited poor outcomes across all fixatives and fixation temperature, with two exceptions, as satisfactory staining results were obtained when using 5% chromic acid. Consequently, Both 10% NBF and 80% emerge as preferred fixatives of choice for glycogen demonstration when coupled with PAS stain. It is noteworthy that Bouin's solution could also provide good outcomes when fixation occurred at 4 °C., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Optimization of antioxidants and angiotensin-converting enzyme (ACE) inhibitory potential gelatin hydrolysate production from Labeo rohita (rohu) swim bladder (SBGH) by alcalase using central composite design (CCD) of response surface methodology (RSM) was investigated. The maximum degree of hydrolysis (DH), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), total antioxidants (TAO), and ACE inhibitory activity were achieved at 0.1:1.0 (w/w) enzyme to substrate ratio, 61 °C hydrolysis temperature, and 94-min hydrolysis time. The resulting SBGH obtained at 19.92% DH exhibited the DPPH (24.28 µM TE/mg protein), ABTS (34.47 µM TE/mg protein), TAO (12.01 µg AAE/mg protein), and ACE inhibitory (4.91 µg/mg protein) activity. Furthermore, SBGH at 100 µg/ml displayed osteogenic property without any toxic effects on MC3T3-E1 cells. Besides, the protein content of rohu swim bladder gelatin (SBG) and SBGH was 93.68% and 94.98%, respectively. Both SBG and SBGH were rich in glycine, proline, glutamic acid, alanine, arginine, and hydroxyproline amino acids. Therefore, SBGH could be an effective nutraceutical in functional food development., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

From extraction experiments, the exchange extraction constants corresponding to the general equilibriums M+ (aq) + NaL+ (org) ⇔ ML+ (org) + Na+ (aq) or M+ (aq) + CsL+ (org) ⇔ ML+ (org) + Cs+ (aq), which take place in the two-phase water–nitrobenzene extraction system (M+ = Li+, H3O+, Ag+, K+, NH4+, Tl+, Rb+; L = calix[4]arene-bis crown5(1,3-alternate), 26,28-dipropoxycalix[4]arene-crown-5(1,3-alternate), 11,23-dibromo-25,28-dipropoxycalix[4]arene-crown-5 (1,3-alternate) and 1,3-alternate-25,27-dihydroxycalix[4]arene-crown-5; aq = aqueous phase, org = organic phase), were evaluated. The stability constants of the NaL+ and CsL+ complexes were calculated from the extraction of the respective picrates in the system of water–nitrobenzene solution of L. Further, the stability constants of the ML+ complexes in nitrobenzene saturated with water were determined. High selectivities were found in some systems under study. [ABSTRACT FROM AUTHOR]

Owing to splendid properties, trinitrophenol-based ionic liquid consisting of ammonium–imidazolium cation, 3,5-diamino-1,2,4-triazole picrate (DATPA), has been investigated concerning the thermal stability in this study. Differential scanning calorimeter (DSC) and thermogravimetry (TG) are used to explore the thermal behavior such as melting point, decomposition temperature, and the temperature of 10% mass loss which are the target to evaluate the thermal stability of other two picrates (picrate and 4-amino-1,2,4-triazole picrate). The results show that DATPA has better thermal stability at 251–252 °C than the other two picrates, and the melt volatility has decreased as well. Moreover, thermal kinetics parameters are calculated by changing the heating rates of DSC and TG. ASTM standard E698 and Kissinger methods are utilized to calculate, and double extrapolation is accepted to explore the mechanism function in the decomposition course, which has been defined as f (α) = 2.105 (1 - α) [ ln (1 - α) ] 0.525 in this study. Finally, an accelerating rate calorimeter is employed to study the thermal hazard of DATPA under the adiabatic condition and evaluate the level of runaway reaction through the risk matrix. According to Townsend method, we achieve the thermal kinetics parameters of DATPA under adiabatic condition. The results show that the apparent activation energy (Ea) of DATPA is 273.2 kJ mol−1 higher than many other explosives. Besides, according to the theoretical calculation, we find that DATPA has good detonation properties with high stability. [ABSTRACT FROM AUTHOR]

Explosives are perilous and noxious to aquatic biota disrupting their endocrinal systems. Supplementarily, they exhibit carcinogenic, teratogenic and mutagenic effects on humans and animals. Henceforth, the current study has been targeted to biotransform the explosive, 2, 4, 6 trinitrophenol (TNP) by wetland peroxidase from Streptomyces coelicolor. A total peroxidase yield of 20,779 mg/l with 51.6 folds of purification was observed. In silico molecular docking cum in vitro appraisals were accomplished to assess binding energy and interacting binding site residues of peroxidase and TNP complex. TNP required a minimal binding energy of-6.91 kJ/mol and was subjected to biodeterioration (89.73%) by peroxidase in purified form, with 45 kDa and a similarity score of 34 by MASCOT protein analysis. Moreover, the peroxidase activity was confirmed with Zymogram analysis. Characterization of peroxidase revealed that optimum values of pH and temperature as 6 and 40 °C, respectively, with their corresponding stability varying from 3.5 to 7. Interestingly, the kinetic parameters such as K m and V max on 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and H 2 O 2 were 19.27 µm and 0.41 µm/min; 21.4 µm and 0.1 µm/min, respectively. Among the diverse substrates, chemicals and trace elements, ABTS (40 mM), citric acid (5 mM) and Fe 2+ (5 mM) displayed the highest peroxidase activity. Computational docking and in vitro results were corroborative and UV-Vis spectroscopy, HPLC, FTIR and GC-MS indicated the presence of simple metabolites of TNP such as nitrophenols and benzoquinone, showcasing the efficacy of S. coelicolor peroxidase to biotransform TNP. Henceforth, the current study offers a promising channel for biological treatment of explosive munitions, establishing a sustainable green earth., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

A fluorescent dansyl-based amphiphilic probe, 5-(dimethylamino)-N-hexadecylnaphthalene-1-sulfonamide (DLC), was synthesized and characterized to detect multiple analytes at different sensing environments. In acetonitrile, DLC detects nitro explosives such as trinitrophenol (TNP) and 2,4-dinitrophenol (2,4-DNP) by an emission "on-off" response method, and the detection limits (LOD) were estimated to be as low as 4.3 µM and 17.4 µM, respectively. Amphiphilic long chains of the probe were embedded into lipid bilayers to form nanoscale vesicles DLC.Ves. Nanovesicular probe DLC.Ves was found to be highly selective for Hg 2+ among other metal ions and for pyrophosphate (PPi) ions among various anions. DLC.Ves could detect Hg 2+ with a turn "on-off" emission and PPi with ratiometric change in emission at 525 nm. It is proposed that DLC.Ves could detect Hg 2+ via the Hg 2+ -induced aggregation quenching mechanism and PPi through the Hydrogen bonding. The LODs are estimated as 6.41 µM and 70.9 µM for Hg 2+ and PPi, respectively. 1 H NMR, SEM, and fluorescence lifetime measurements confirmed the binding mechanism. Thus, it is believed that the simple fluorescent probe DLC could be a prominent sensor to detect multiple analytes depending on the sensing medium., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

High levels of unconjugated bilirubin (UB) in serum lead to asymptomatic and neonatal jaundice and brain dysfunctions. Herein, we have reported the detection of UB at as low as 1 μM in an aqueous alkaline medium using a Zn(II) complex. The specificity of the complex has been validated by the HPLC in the concentration window 6-90 μM, which is rare. The sensory response of the probe at physiological pH against nitro explosives developed it as an instant-acting fluorosensor for picric acid (PA) and 2,4-dinitrophenol (2,4-DNP). Spectroscopic titration provided a binding constant of 4×10 5  M -1 with PA. The naked eye detection was found to be 15 μM. The solid-state photoluminescent nature of the complex enabled it for PA sensing in the solid phase. Interestingly, the probe remained fluorescent in various volatile and non-volatile organic solvents. As a result, it can also detect PA and 2,4-DNP in a wide range of common organic media. NMR studies revealed the coordination of PA, 2,4-DNP, and UB to the Zn(II) center of the probe, which is responsible for the observed quenching of the probe with the analytes., (© 2023 Wiley-VCH GmbH.)

German chamomile is one of the most effective herbal elements used in anti-allergic products and as an antioxidant. Herein, the antioxidant activity of different extract fractions of German chamomile was initially evaluated using an off-line 2,2-diphenyl-1-picrylhydrazyl spectrophotometric assay. The ethyl acetate extract demonstrated the highest efficacy in scavenging free radicals. Based on this, a rapid screening and separation method using ultra-high-performance liquid chromatography combined with the 2,2-diphenyl-1-picrylhydrazyl assay was implemented to identify antioxidants in the ethyl acetate fraction of German chamomile flowers. Ten potential radical scavengers were tentatively screened from German chamomile using a target-guided isolating approach with off-line two-dimensional high-speed countercurrent chromatography and the structures of the compounds were analyzed and identified. Ultimately, 10 radical scavengers were obtained from the ethyl acetate extract with a purity quotient exceeding 90%. The results demonstrated the effectiveness and reproducibility of this method for isolating potential antioxidants from complex mixtures in a targeted manner. This strategy can be applied to the target-guided isolation of complex mixtures of natural products with broad K-values and similar structures., (© 2024 Wiley-VCH GmbH.)

Background: Heterocyclic materials-containing thiazoles exhibited incredible importance in pharmaceutical chemistry and drug design due to their extensive biological properties., Methods: Synthesis of thiazoles and bis-thiazoles from the reaction of 2-((6-Nitrobenzo[ d][1,3]dioxol-5-yl)methylene)hydrazine-1-carbothioamide with hydrazonoyl chlorides in dioxane and in the existence of triethylamine as basic catalyst. The antioxidant, in vitro antiproliferative, and cytotoxicity efficacy of thiazoles and bis-thiazoles were measured., Results: In this work, novel series of 5-methyl-2-(2-(-(6-nitrobenzo[d][1,3]dioxol-5-yl)methylene) hydrazinyl)-4-(aryldiazenyl)thiazoles (4a-f) were prepared via the reaction of hydrazonoyl chlorides 2a-f with 2-((6-nitrobenzo[d][1,3]dioxol-5-yl)methylene)hydrazine-1-carbothioamide (1) in dioxane and employing triethylamine as basic catalyst. Following the same procedure, bisthiazoles (6, 8, and 10) have been synthesized by utilizing bis-hydrazonoyl chlorides (5, 7, and 9) and carbothioamide 1 in a molar ratio (1:2), respectively. The distinctive features in the structure of isolated products were elucidated by spectroscopic tools and elemental analyses. The antioxidant, in vitro anti-proliferative, cytotoxicity, and anti-cancer efficacy of thiazoles and bis-thiazoles were evaluated. Compounds 4d and 4f were the most potent antioxidant agents. Gene expression of apoptosis markers and fragmentation assay of DNA were assessed to explore the biochemical mechanism of synthesized products. Thiazoles significantly inhibited cell growth and proliferation more than bis-thiazoles. They induced apoptosis through induction of apoptotic gene expression P53 and downregulation of antiapoptotic gene expression Bcl-2. Moreover, they induced fragmentation of DNA in cancer cells, indicating that they could be employed as anticancer agents by inhibiting tumor growth and progression and can be considered effective compounds in the strategy of anti-cancer agents' discovery., Conclusion: Synthesis, DPPH Radical Scavenging, Cytotoxic activity, and Apoptosis Induction Efficacy based on Novel Thiazoles and Bis-thiazoles., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Reactions of lanthanide chlorides or trifluoracetates (tfa) or picrates with trimethylphosphate alone in the first two cases or trimethylphosphate plus 1,10-phenanthroline or 2,2′;6′,2′′-terpyridine in the third, result in the formation of crystalline products containing dimethylphosphate (dmp–). Single crystal X-ray structural characterisation of these materials has shown that the stoichiometrically simple Ln(dmp)3 species obtained with chloride reactants and the lighter lanthanides are polymeric and commonly dimorphic, while the stoichiometrically more variable mixed dmp/tfa complexes have structures closely related to one phase of the Ln(dmp)3 family, and the presence of picrate and aza-aromatic ligands enables the isolation of Y and Lu derivatives containing binuclear species. In all, the dmp– ligands adopt exclusively the κ1 O ;κ1 O′ bridging mode, the overall results indicating that this should apply to the complete lanthanide series. Structural studies of the products of reaction of different lanthanide(III) salts with trimethylphosphate show them to contain dimethylphosphate as a bridging bidentate rather than a chelate ligand across the lanthanide series. [ABSTRACT FROM AUTHOR]

Reactions of the lanthanide(iii) picrates (picrate = 2,4,6-trinitrophenoxide = pic) with 1,10-phenanthroline (phen) and 2,2′:6′,2′′-terpyridine (terpy) in a 1 : 2 molar ratio have provided crystals suitable for X-ray structure determinations in instances predominantly involving the lighter lanthanides. In all, the aza-aromatic ligands chelate the lanthanide ion, none being found as 'free' ligands within the lattice. The complexes of 1,10-phenanthroline have been characterised in two forms, one unsolvated (Ln = La, Sm, Eu; monoclinic, C 2/ c , Z 8), one an acetonitrile monosolvate (Ln = Gd; monoclinic, P 21/ a , Z 4), the latter being the only previously known form (with Ln = La). In both forms, the LnIII is nine-coordinate, in an approximately tricapped trigonal-prismatic environment, with two picrate ligands chelating through phenoxide and 2-nitro group oxygen atoms, the third being bound through phenoxide-O only. The 2,2′:6′,2′′-terpyridine complexes, all acetonitrile monosolvates defined for Ln = La, Gd, Er, and Y (monoclinic, C 2/ c , Z 4), are ionic, one picrate having been displaced from the primary coordination sphere. For Ln = La, the two bound picrates are again chelating, making the LaIII 10-coordinate in a distorted bicapped square-antiprismatic environment but in the other species they are bound through phenoxide-O only, making the LnIII ions eight-coordinate in a distorted square-antiprismatic environment. Stacked arrays of the ligands can be found in both series of complexes, with intramolecular picrate–picrate and picrate–aza-aromatic stacks being prominent features. Structure determinations on complexes of lanthanide(III) picrates with aza-aromatic ligands provide examples of various stacking arrays. The chain of [La(terpy)2(pic)2]+ cations (shown in space-filling mode) present in the lattice of [La(terpy)2(pic)2](pic)·CH3CN involves both intra- and intermolecular heterogeneous stacks. [ABSTRACT FROM AUTHOR]

The carboxamide-O donor ligands dimethylacetamide (dma) and N -methylpyrrolidinone (nmp) form complexes of lanthanide picrates, Ln(pic)3, of stoichiometry Ln(pic)3(carboxamide)3 in a remarkable variety of phases. Complexes [Ln(pic)3(dma)3], Ln = La, Ce, Nd, Sm, Gd, Yb, Lu, and Y, adopt the 9-coordinate molecular form of tricapped trigonal-prismatic coordination geometry seen to predominate, as two stereoisomers, in related species involving dimethylsulfoxide (dmso), trimethylphosphate (tmp), and hexamethylphosphoramide (hmpa) but as four different phases (depending on Ln), none of which is the same as for the previously known La complex. For Ln = Pr, 9-coordinate species of composition [Pr(pic)3(dma)2(alcohol)] (alcohol = ethanol and propan-2-ol) have been characterised and a low quality determination indicates that a similar species (with propan-2-ol) is formed by Y. For nmp, the composition [Ln(pic)3(nmp)3] is maintained across the series for Ln = La, Ce, Pr, Nd, Gd, Er, Tm, Yb, and Lu but 9-coordination is not for Ln = Er, Tm, Yb, and Lu. A decreased coordination there is a result of one or two picrate ligands acting as phenoxide-O donors only, a marked contrast with the analogous Ln(pic)3 complexes with dmso, tmp, hmpa, and dma, where picrate chelation is universal, but with some parallel to related ScIII complexes. Several polymorph pairs can be identified among the nmp complexes. Structural studies of the adducts of lanthanide picrates with dimethylacetamide (dma) and N-methylpyrrolidinone (nmp) add further variety to the nature of simple O-donor ligand complexes of these picrates. Polymorphism is readily detected in the dma complexes, while, with the heavier lanthanides, nmp causes partial detachment of the picrate ligands. [ABSTRACT FROM AUTHOR]

Adducts of dimethylsulfoxide, dmso = Me2SO, with lanthanide(iii) picrates (picrate = 2,4,6-trinitrophenoxide, pic) of stoichiometry Ln(pic)3·3dmso have been prepared and characterised by single-crystal X-ray structure determinations as discrete, neutral, mononuclear molecular species. Such complexes have been obtained across the gamut of Ln, specifically for Ln = La, Pr, Nd, Sm, Gd, Dy, Yb, Lu, and Y, presumably also accessible for other intermediate members, the series being isomorphous (monoclinic, C 2/ c , Z = 8); a second triclinic P CH19169_IE1.gif form has also been identified for Ln = La, Pr. In both forms, the metal atom coordination environments are nine-coordinate, tricapped trigonal prismatic, [Ln(dmso- O)3(pic- O,O′)3], two of the three unidentate ligands lying in one of the trigonal planes and one in the other (an isomer we have termed meridional, mer). A hydrated form of Ln(pic)3·2dmso·H2O stoichiometry has also been defined for Ln = Sm, Gd, Lu, the metal atom environment again nine-coordinate, [Ln(dmso- O)2(H2 O)(pic- O,O′)3], but now fac , with the three unidentate ligands occupying one triangular face of the tricapped trigonal prism and involved in a centrosymmetric H-bonding array with the three similar ligands of an adjacent complex; the three capping atoms are nitro-oxygen atoms, the phenoxy- O triad occupying the other face. Structural characterisation of adducts of lanthanide picrates with dimethylsulfoxide has provided evidence that the 9-coordinate, tricapped trigonal-prismatic, mer -[Ln(pic)3(dmso)3] form with chelating picrate ligands may extend through the full series. Partial aquation of the tris(dmso) complexes to [Ln(pic)3(dmso)2(OH2)] provides three examples of an otherwise similar but facial isomer. [ABSTRACT FROM AUTHOR]

Crystalline products of the reactions of lanthanide picrates, Ln(pic)3 (pic = 2,4,6-trinitrophenoxide), with hexamethylphosphoramide (hmpa) and octamethylpyrophosphoramide (ompa) have been characterised by single-crystal X-ray diffraction studies. With hmpa and lighter lanthanides (La, Sm, Eu), isomorphous species (monoclinic, P 21/ c , Z 4) of stoichiometry [Ln(pic)3(hmpa)3]·0.5H2O, have been defined where the molecular units in the lattice contain 9-coordinate Ln with tricapped trigonal-prismatic coordination geometry. The picrate ligands are bidentate through phenoxide-O and 2-nitro-O, with the latter occupying the capping positions, while the hmpa ligands are singly O-bound to one trigonal face. Heavier lanthanides (Gd, Lu) and Y have been found to give isomorphous (monoclinic, P 21/ n , Z 4) species of stoichiometry [Ln(pic)3(hmpa)2], with 8-coordinate Ln of an irregular geometry best considered as close to that of a bicapped trigonal-prism. The picrate ligands chelate in the same manner as in the lighter Ln complexes but with one spanning a trigonal edge, and the hmpa-O donors occuping two apices of the other trigonal face. The ligand ompa has been found to act as a bidentate chelate in all isolated species, displacing one picrate from the metal ion coordination sphere to give ionic complexes. For La, Nd, and Gd, isomorphous (monoclinic, P 21/ n , Z 4) complexes of stoichiometry [Ln(pic)2(ompa)2(OH2)](pic)·0.5H2O containing 9-coordinate, tricapped trigonal-prismatic Ln with a single aqua ligand have been defined, while for Er, Yb, Lu, and Y, both the coordinated and lattice water molecules are lost in isomorphous (monoclininc, P 21/ c , Z 8) 8-coordinate, square-antiprismatic species of stoichiometry [Ln(pic)2(ompa)2](pic). For Er, further polymorphs, one monoclinic, P 21/ c , and the other triclinic, CH19251_IE1.gif , have also been characterised. Structural studies of adducts of the lanthanide picrates with hexamethylphosphoramide (hmpa) and octamethylpyrophosphoramide (ompa) provide significant contrasts with those of analogous adducts with dimethylsulfoxide and trimethylphosphate. Adducts of hmpa show a transition from 9-coordinate (hmpa)3 to 8-coordinate (hmpa)2 species, while ompa displaces one picrate from the primary coordination sphere. [ABSTRACT FROM AUTHOR]

Addition of various oxygen-donor ligands (L, all dipolar, aprotic solvents), to a solution of hydrated scandium picrate in weakly coordinating solvents (S), has yielded several crystalline adducts of the form Sc(pic)3(L) m (· n S) in which all ligands L are coordinated, subsequently characterised by a series of single crystal X-ray studies. For L = dmso, m = 3 and the picrate anions are all bound as phenoxide-O donor units, while for nmp, dma, tmp, and hmpa, m = 2 and one of the bound picrates becomes bidentate through phenoxide- and nitro-O donation. For L = ompa, m = 2 and two picrate ligands are bound through phenoxide-O while one is displaced from the primary coordination sphere. All complexes contain six-coordinate ScIII, confirming that this coordination number is a consequence of ligand bulk. Six-coordination of ScIII is observed throughout in crystalline adducts of scandium picrate with dmso, dma, nmp, tmp, hmpa, and ompa, although with variations in the adduct stoichiometry and the coordination mode of picrate. [ABSTRACT FROM AUTHOR]

This work discusses the synthesis and characterization of some of the thermodynamically stable energetic materials of c (3), t (3)-dimethyl-r(2), c (6)-diarylpiperidin-4-one picrates which are the analogues of the explosive D "The Dunnite". c (3), t (3)-Dimethyl-r(2), c (6)-diarylpiperidin-4-one picrates have been synthesized by reacting c (3), t (3)-dimethyl-r(2), c (6)-diarylpiperidin-4-ones with picric acid in ethanol medium at room temperature. Spectral methods like IR, 1H NMR and 13C NMR were used to characterize the synthesized compounds. Subsequently the explosive properties of the synthesized compounds were studied with the standard equations and compared with that of LOTUSES code simulated results. The calculated physiochemical properties of these energetic materials are compared with that of picric acid and Dunnite. The addition of piperidone moiety into picric acid helps in controlling and mitigating the risk of the hazardous nature of the energetic materials. Image 1 • Seven piperidin-4-one picrates were synthesized and characterized. • The compounds 1–7 prefer to exist in a chair conformation. • Energetic properties were studied using computer stimulated LOTUSES code. • VoD of few piperidone picrates fulfill the criteria of highly energetic compounds. • The piperidone picrates are highly stable. [ABSTRACT FROM AUTHOR]

Three 3-ethyl-5-methyl-2,6-diarylpiperidin-4-on-1-ium picrates (1–3) (aryl = C6H5, p-FC6H4 and p-CH3OC6H4,) have been synthesized by mixing 3-ethyl-5-methyl-2,6-diarylpiperidin-4-one and picric acid. The synthesized compounds were characterized by elemental analysis, FT-IR spectroscopy and NMR spectroscopy. The obtained conformation of compound 3 was determined by single crystal XRD analysis. The crystallographic data revealed that the spatial structure of the title crystals adopted a chair conformation. Additionally, the synthesized compounds 1–3 were subjected to UV-visible, fluorescence and DFT studies for a better understanding of the molecular design and optoelectronic properties. The optimized geometric parameters were in agreement with the corresponding experimental values. The Mulliken and MEP analyses were utilized to spot the reactive sites of the compounds. The intermolecular and intramolecular delocalization and donor–acceptor interactions were ensured by the NBO analysis. The calculated HOMO and LUMO energies exhibited that the charge transfer happened within the molecule. The polarizability and hyperpolarizability values showed that the compounds possessed a non-linear optical nature. [ABSTRACT FROM AUTHOR]

Symmetric bisimidazolium picrates were synthesized by the quaternization of bisimidazolylmethylene and a metathesis reaction with silver picrate. The symmetric structures of the new picrate salts were confirmed by 1H and 13C NMR spectral analysis and ESI‐MS. The structures of compounds 3a and 4a were also confirmed by X‐ray single crystal diffusion. The thermal properties of the compounds were determined by differential scanning calorimetry and thermogravimetric analysis. The picrates showed better thermal stabilities than did traditional azolium‐based ionic salts, with higher decomposition temperatures, and 3b had the lowest melting point. These results indicated that the electronic effect of the substituent groups obviously influenced the quaternization and the high‐energetic properties. [ABSTRACT FROM AUTHOR]

Single crystals of amino (2-(propan-2-ylidene) hydrazinyl) methaniminium picrate (APHMP) were grown and crystallized at room temperature by slow evaporation-solution growth technique. The structure of the APHMP was confirmed by single crystal X-ray diffraction analysis and various spectroscopic techniques like FT-IR, 1 H and 13 C NMR. The optical quality of the crystal was evaluated through UV–vis absorption, UV–vis–NIR transmittance, photoluminescence. The compound was thermally stable up to 203 °C. The molecular structure was optimized using B3LYP method using 6-311G(d,p) basis set. The energy gap between HOMO and LUMO in APHMP is 3.46 eV. [ABSTRACT FROM AUTHOR]

Two new picrate salts, namely, 1, 4-diaza bicyclo(2,2,2)octanium picrate [DABCOP] and Furan-2yl methanaminium picrate [FMP] has been successfully crystallized by Slow Evaporation Solution growth Technique (SEST). The crystal and molecular structures have been determined by single crystal X-ray diffraction method. The crystal packings of the both the crystals feature classical N H⋯O hydrogen bonds and C H⋯O interactions. In DABCOP, each diaza molecule is linked to the picric acid which forms cyclic R 4 4 (19) and R 4 4 (18) motifs. In FMP, most of the ortho related nitro group in anion are involved in N H⋯O hydrogen bonding network forming five ring R 1 2 (6), R 2 1 (4), R 2 4 (4), R 1 2 (6), and R 2 2 (5) motifs. Also, a weak C H⋯O interaction forming a dimer R 2 2 (8) motif with donor-acceptor distance of 3.413(2) Å. Based on the Hartree-Fock (HF) and Density Functional Theory (DFT) method with 6–311++G (d,p) basis set, the molecular vibrational bands were interpreted. HOMO and LUMO analysis of the molecules were calculated using corresponding methods with the same basis set. In addition, Mulliken charge analysis and thermodynamic properties were calculated. Hirshfeld surface analysis and associated two dimensional fingerprint plots show intermolecular contacts and their relative contribution via colored contour approach. [ABSTRACT FROM AUTHOR]