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Very metal-poor massive stars hold the key to interpret high-redshift star-forming galaxies and the early reionization epoch, but also contemporary events such as gravitational waves. To study these objects in resolved environments, we need to resort to dwarf irregular galaxies far from the potential wells of M31 and the Milky Way, and therefore distant. While the archives, recently boosted by the ULLYSES and XSHOOTU programs, store a healthy dataset of massive stars in the Milky Way and the Magellanic Clouds, the number of observed targets with poorer metal content than the SMC (1/5 Zȯ) is dramatically small. This paper reviews the state of observations of very metal-poor massive stars, assessing what can be realistically learned about their physics and evolution with current instrumentation, and arguing whether or not near-future facilities can remedy the gaps in the knowledge that remain. [ABSTRACT FROM AUTHOR]

Chemical investigation of the EtOAc extract from the aerial parts of Acrostichum aureum distributed along coastlines of Vietnam lead to the isolation of a new ecdysteroid, named pterosterone 20,22-acetonide (1), along with twelve known compounds (2-13). Their structures were elucidated by spectroscopic methods including 1D, 2D NMR and HR-ESI-MS analysis as well as comparison with the results of previous studies. Five ecdysteroids (1-5) were evaluated for their cytotoxic activity against the LU-1, MCF7 and HepG2 human cancer cell lines using the SRB assay. Ecdysteroids 1 and 2 having a 20,22-dimethyl acetal group showed cytotoxicity against all tested cell lines with IC50 values in the range 51.59 to 60.14 µM. The other compounds were considered as inactive in this test. [ABSTRACT FROM AUTHOR]

Copyright of Santo: Rivista Francescana di Storia Dottrina Arte is the property of Associazione Centro Studi Antoniani and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Natural Fe2+-rich princivalleite was thermally treated in the air at 700 °C to study crystal-chemical and color variations due to changes in oxidation states of Fe and Mn and atom ordering. Overall, the experimental data (electron microprobe, structural refinement, Mössbauer, infrared, and optical absorption spectroscopy) show that thermal treatment of princivalleite results in an almost total Fe2+ oxidation to Fe3+ and an oxidation of approximately one-third of Mn2+ to Mn3+ along with a minor degree of disorder of Al–Fe–Mn over the Y and Z sites. This process is accompanied by a significant deprotonation of the sample. The YFe and YMn oxidation from + 2 to + 3 yields in a decrease in a-parameter, whereas the increased content of ZFe3+ results in a minor increase in the c-parameter. Optical absorption spectroscopy shows that the faint blue (azure) color of untreated princivalleite is caused by the presence of Fe2+ and the absence of Ti4+. Thermal treatment in air (700 °C) changed the color to dark brown due to the progressive oxidation of Fe2+ to Fe3+ and Mn2+ to Mn3+, as demonstrated by the evolution of optical absorption bands caused by electron transitions in these 3d-cations. However, the most evident result of the thermal treatment of the Fe-rich princivalleite sample is the simultaneous presence of Fe2+, Fe3+, Mn2+, and Mn3+, with a Fe3+/ΣFe and Mn3+/ΣMn ratio of 0.92 and 0.25, respectively. This observation suggests that the oxidation process during the heating experiments was largely controlled by kinetic factors. [ABSTRACT FROM AUTHOR]

Featured Application: The specific application of this work lies in the new avenue synthesis of nanomedicines—particularly Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs—using eco-friendly methods. These nanoparticles have shown significant potential as they can be used for potent antioxidant and antibacterial activities. The use of Beta vulgaris extract for the bio-reduction process adds to the environmentally sustainable aspect of the research. Furthermore, the antioxidant activity of the nanoparticles supports their potential medical applications beyond antibacterial therapy. Additionally, the study paves the way for future research into utilizing nature-inspired approaches for green and effective medical advancements. The synthesis of novel nanomedicines through eco-friendly protocols has been applied on a large scale with the prediction of discovering alternate therapies. The current work attained phytogenic synthesis of Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs through bio-reduction using an aqueous extract of Beta vulgaris (red beetroot). The phytochemical profile of the eco-friendly synthesized metallic/bimetallic nanoparticles was studied. The optical properties of nano-solutions were studied via UV-visible spectroscopy. The Fourier-transform infrared spectroscopy (FT-IR) spectral analyses revealed that stretching vibrations at wavenumbers 3303.81–3327.81 cm−1 attributed to phenolic hydroxyl groups documented shifts in the values in this range owing to proton dissociation through the bio-reduction of the metal ions. The surface morphology and the charge of the nanoparticles were investigated using a Transmission Electron Microscope (TEM) and zeta potential analyses. The prepared nano-solutions showed lower antioxidant activity (1,1-Diphenyl-2-picrylhydrazyl (DPPH•) and phosphomolybdate assays) than the plant extract. These results together with phytochemical analyses support the participation of the reactive species (phenolic contents) in the bio-reduction of the metal ions in the solutions through the formation of metallic/bimetallic nanoparticles. Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs showed antibacterial potentiality. AgSeO2-bmNPs were superior with inhibitory zone diameters of 34.7, 37.7, 11.7, and 32.7 mm against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Salmonella enterica, respectively. Applying the Methylthiazole Tetrazolium (MTT) assay, the Ag-TiO2 bmNPs revealed potent cytotoxicity against the HePG2 tumor cell line (IC50 = 18.18 ± 1.5 µg/mL), while Ag-SeO2 bmNPs revealed the most potent cytotoxicity against the MCF-7 cell line (IC50 = 17.92 ± 1.4 µg/mL). [ABSTRACT FROM AUTHOR]

Abstract Computational tools in investigating of spectral heterocyclic compounds ranges based on pyrimidine‑2‑thiones, take some importance in identifying their molecular and electronic behavior. Some charcoal heterocyclic compounds were previously synthesized in our laboratory and their experimental results were compared with the computational evaluation. Computational spectroscopic analytical items (IR, NMR and UV–Vis) were calculated using the more popular DFT methods and the predicted results were compared with the reported experimental ones. Quantum and chemical parameters were calculated and molecular electrostatic surface potential (MEP) was studied which predicted the highly electronic sites around the compounds. Some molecular properties (ionization energy, electron affinity, energy gap, hardness, electronegativity, electrophilicity index, static dipole moment and average linear polarizability) of these Schiff bases which were computed at B3LYP/6-31G(d,p) level in aqueous phase. Benchmark analysis was performed for three ab initio functionals such B3LYP, BPV86 and B3PW91 methods to explain the data resulted from NMR spectra. The docking study of some selected previously synthesized compounds was performed using the viral Mpro enzyme protein in compared to a k36 reference ligand inhibitor. The study indicated the ability of the synthesized compounds to form H-bond and hydrophobic (VDW, π-alkyl and π-sulfur) interactions with Mpro enzyme receptor with high inhibition effect of compound L2.

A new unsaturated fatty glycoside Humionoactosides A, together with four known compounds were isolated from the whole plant of Euphorbia humifusa Willd. Their structures were identified by MS/MS, NMR and ECD spectroscopic analyses, and comparison with the literature data. All compounds were evaluated for the effect on melanogenesis and tyrosinase activity use B16 cells in vitro, and the results showed that compound 1 could significantly improve the formation of melanin (138.7%, 50 μM) and tyrosinase activity (137.2%, 50 μM) compared with the positive control 8-MOP (125.2%, 138.9%, 50 μM) in a dose-dependent manner. This is the first time that those compounds reported from Euphorbia humifusa Willd. with potential anti-vitiligo activity. [ABSTRACT FROM AUTHOR]

A previously undescribed sesquiterpene lactone, named eupalinolide N (1), was isolated from traditional Chinese medicine "Ye-Ma-Zhui" (Eupatorium lindleyanum) by ethanol reflux extraction, reduced pressure concentration, macroporous resin column chromatography, and C18 reversed-phase chromatography. Its structure was elucidated by a comprehensive interpretation of spectroscopy evidence as well as ECD calculations. 1 showed anti-inflammatory activity by inhibiting the gene expressions of pro-inflammatory factors including IL-1ß, TNFa COX-2, and iNOS at the concentration of 7.5 µM, as well as attenuating the excretion of NO, IL-6, and TNF-a in Raw 264.7 macrophages at the concentration of 15 µM. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) is the most important factor that affects soil quality. In arid areas, lack of SOM causes a major problem and farmers need to add organic amendments to restore the soil quality. Organic waste composting is an efficient and sustainable way to produce organic resource for soil amendment. The main objective of this study was to evaluate the effectiveness of compost derived from co-composting of date palm residues with goat manure to ameliorate soil quality in arid region in the southeast of Tunisia. Palm tree wastes were co-composted with goat manure (1/3 v:v) for 120 days. Chemical properties and structural changes of humic acids (HA) during the composting process were investigated using physicochemical and spectroscopic analyses: spectroscopic ultraviolet/visible (UV) analysis and Fourier Transform Infrared (FTIR) Spectroscopy. HA fractions extracted from different steps of composting process were monitored by measuring humification ratios CHA/CFA and E4/E6. Soil was amended with produced compost and manure during 3 months, and soil property evolution was evaluated using chemical and spectroscopic analyses. Results revealed that the date palm compost displayed neutral pH, a C/N ratio of about 12 and high levels of nutrients. FTIR spectra of HA extracted from produced compost and manure showed the abundance of aromatic structures with a high condensation and polymerization confirmed by a low E4/E6 ratio related to the increase in polymerization and polycondensation and a high CHA/CFA humification rate that improved the elevation of the humification degree. The application of the produced palm compost in soil improved soil quality by increasing levels of SOM and nutrients and showed a marked improvement of humification rate. The FTIR spectra of soil HA showed a clear increase in aromatic structures that improved soil stability. The input of palm compost is an efficient way to ameliorate arid soil quality by supplying highly humified organic matter restitution. [ABSTRACT FROM AUTHOR]

Elevated blood sugar levels caused by starch digestion was a target for controlling diabetes mellitus. The in vitro and in vivo digestibility of wheat starch was evaluated to find that adding 15 % persimmon leaf extract (PLE) to starch reduced its digestibility by 69.50 % and the peak postprandial blood glucose by 23.63 %. Subsequently, we observed under scanning electron microscopy and atomic force microscopy that the presence of PLE led to the destruction of starch structure and the aggregation of α-glucosidase so as to decrease starch digestion and hinder the binding of starch to α-glucosidase. Through multi-spectral analysis, PLE hindered the clathrate of iodine and starch, and also increased the crystallinity of starch by 48.58 %. For α-glucosidase inhibitory activity (IC 50 = 72.49 μg/mL), PLE preferentially occupied the active center of α-glucosidase, changed its fluorescence characteristics and secondary structure through hydrogen bonding and hydrophobic interaction. Moreover, among the 23 potential α-glucosidase inhibitors screened from PLE, combined with molecular simulation, Procyanidin B2 had the strongest inhibitory effect (IC 50 = 33.22 μg/mL) and binding energy (−7.09 kcal/mol), which was most effectively inhibitory on digestion. These results indicated the potential of PLE in hypoglycemia targeting both starch and α-glucosidase. • Persimmon leaf extract (PLE) effectively delayed starch digestion in vitro and in vivo. • Clarify how PLE upraised the ordered crystal structure of starch. • PLE inhibited α-glucosidase through hydrogen bonding and hydrophobic interactions. • Procyanidin B2 showed the strongest inhibition among the 23 PLE-derived inhibitors. • Hypoglycemic effect of PLE was due to its dual action on starch and α-glucosidase. [ABSTRACT FROM AUTHOR]

Computational tools in investigating of spectral heterocyclic compounds ranges based on pyrimidine‑2‑thiones, take some importance in identifying their molecular and electronic behavior. Some charcoal heterocyclic compounds were previously synthesized in our laboratory and their experimental results were compared with the computational evaluation. Computational spectroscopic analytical items (IR, NMR and UV–Vis) were calculated using the more popular DFT methods and the predicted results were compared with the reported experimental ones. Quantum and chemical parameters were calculated and molecular electrostatic surface potential (MEP) was studied which predicted the highly electronic sites around the compounds. Some molecular properties (ionization energy, electron affinity, energy gap, hardness, electronegativity, electrophilicity index, static dipole moment and average linear polarizability) of these Schiff bases which were computed at B3LYP/6-31G(d,p) level in aqueous phase. Benchmark analysis was performed for three ab initio functionals such B3LYP, BPV86 and B3PW91 methods to explain the data resulted from NMR spectra. The docking study of some selected previously synthesized compounds was performed using the viral Mpro enzyme protein in compared to a k36 reference ligand inhibitor. The study indicated the ability of the synthesized compounds to form H-bond and hydrophobic (VDW, π-alkyl and π-sulfur) interactions with Mpro enzyme receptor with high inhibition effect of compound L2. [ABSTRACT FROM AUTHOR]

The synthesis of novel nanomedicines through eco-friendly protocols has been applied on a large scale with the prediction of discovering alternate therapies. The current work attained phytogenic synthesis of Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs through bio-reduction using an aqueous extract of Beta vulgaris (red beetroot). The phytochemical profile of the eco-friendly synthesized metallic/bimetallic nanoparticles was studied. The optical properties of nano-solutions were studied via UV-visible spectroscopy. The Fourier-transform infrared spectroscopy (FT-IR) spectral analyses revealed that stretching vibrations at wavenumbers 3303.81–3327.81 cm−1 attributed to phenolic hydroxyl groups documented shifts in the values in this range owing to proton dissociation through the bio-reduction of the metal ions. The surface morphology and the charge of the nanoparticles were investigated using a Transmission Electron Microscope (TEM) and zeta potential analyses. The prepared nano-solutions showed lower antioxidant activity (1,1-Diphenyl-2-picrylhydrazyl (DPPH•) and phosphomolybdate assays) than the plant extract. These results together with phytochemical analyses support the participation of the reactive species (phenolic contents) in the bio-reduction of the metal ions in the solutions through the formation of metallic/bimetallic nanoparticles. Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs showed antibacterial potentiality. AgSeO2-bmNPs were superior with inhibitory zone diameters of 34.7, 37.7, 11.7, and 32.7 mm against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Salmonella enterica, respectively. Applying the Methylthiazole Tetrazolium (MTT) assay, the Ag-TiO2 bmNPs revealed potent cytotoxicity against the HePG2 tumor cell line (IC50 = 18.18 ± 1.5 µg/mL), while Ag-SeO2 bmNPs revealed the most potent cytotoxicity against the MCF-7 cell line (IC50 = 17.92 ± 1.4 µg/mL).

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two new arabinofuranosidetridecanol, namely 1,2-tridecanediol-1-O-α-L-5'-acetylarabinofuranoside (1) and 1,2-tridecanediol-1-O-α-L-arabinofuranoside (2) together with known compound, 1,2-tridecanediol (3) were isolated from Commiphora merkeri exudate. Compound 1 showed larvicidal activity against Ae. aegypti (LC50 = 40.66 µg/mL), An. gambiae (LC50 = 22.86 µg/mL) and Cx. quinquefasciatus (LC50 = 15.88 µg/mL). Also, Compound 2 had larvicidal activity against Ae. aegypti (LC50 = 33.79 µg/mL), An. gambiae (LC50 = 31.99 µg/mL) and Cx. quinquefasciatus (LC50 = 17.70 µg/mL). There were no significant difference of larvae mortalities (≥ 95%) among the two compounds and among mosquito species except for compound 2 at 72 h for Cx. quinquefasciatus and An. gambiae. Compound 3 was not larvicidal active even after 72 h of exposure time. In addition, none of the compound was cytotoxic to brine shrimps. The two Arabinofuranosidetridecanol are potential against mosquito species and they could be safe in the environment. [ABSTRACT FROM AUTHOR]

Three phenolic compounds (±1 and 2) including a pair of new enantiomers were isolated from the sclerotia of Inonotus obliquus. Their structures were assigned by extensive spectroscopic analyses. All the compounds were evaluated for the neuroprotective activity against oxidative damage on human neuroblastoma SH-SY5Y cells induced by H2O2. Compound 2 showed remarkable neuroprotective effect and significantly improved the cell viability of SH-SY5Y cells treated by H2O2. [ABSTRACT FROM AUTHOR]

Very metal-poor massive stars hold the key to interpret high-redshift star-forming galaxies and the early reionization epoch, but also contemporary events such as gravitational waves. To study these objects in resolved environments, we need to resort to dwarf irregular galaxies far from the potential wells of M31 and the Milky Way, and therefore distant. While the archives, recently boosted by the ULLYSES and XSHOOTU programs, store a healthy dataset of massive stars in the Milky Way and the Magellanic Clouds, the number of observed targets with poorer metal content than the SMC (1/5 Zȯ) is dramatically small. This paper reviews the state of observations of very metal-poor massive stars, assessing what can be realistically learned about their physics and evolution with current instrumentation, and arguing whether or not near-future facilities can remedy the gaps in the knowledge that remain. [ABSTRACT FROM AUTHOR]

Successful preparation of Schiff base 4‐(4‐aminophenoxy)‐N‐(1‐(pyridin‐2‐yl)ethylidene)aniline derived from refluxing of 4,4‐oxydianniline with 2‐acetylpyridine within 2 h in 1:1 molar ratio was performed. Different transition metal complexes were synthesized by reacting metal chlorides with the formed ligand in 1:1 molar ratio. Structural features of the complexes were obtained from different tools such as infrared (IR), 1H‐nuclear magnetic resonance (1H‐NMR), ultraviolet–visible (UV‐vis), molar conductivity, thermogravimetric (TG)/differential thermogravimetric (DTG), microanalysis, and mass spectrometry. All complexes had an octahedral structure and Schiff base acted as a neutral bidentate ligand that linked to metal centers via N‐azomethine and N‐pyridine atoms. Cr(III), Fe(III), and Ni(II) complexes were electrolytes while other complexes were nonelectrolytes. The molecular structure of Schiff base was optimized theoretically and its HOMO and LUMO energies were dictated by B3LYP/DFT calculations. The in vitro antibacterial activity versus some selected bacteria species showed that all prepared compounds were biologically active except Fe(III) complex against certain species and Co(II) complex had the highest biological activity values. Molecular docking was used to determine effective binding modes between ligand and its [Co(L)(H2O)2Cl2]·4H2O complex with active sites of 4WJ3, 4ME7, 4K3V, and 3T88 receptors. The strongest binding of Co(II) complex was with the 4ME7 receptor with lowest binding energy value −25.4 kcal mol−1. Schiff base as corrosion inhibitors for mild steel in 1.0‐M HCl had been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PP), and electrochemical frequency modulation (EFM). The results showed that the inhibitor acts as a mixed‐type inhibitor. The inhibition efficiency increases with increasing inhibitor concentration to its maximum of 97.5% at 1 × 10−3 M solution. The adsorption model obeys the Langmuir isotherm, and Gibbs free energy was around −40 kJ/mol, indicating that it is spontaneously and chemically adsorbed on the surface. SEM/EDX results proved the sticking of a barrier film on the mild steel sample. [ABSTRACT FROM AUTHOR]

Novel Schiff base ligand was prepared by the condensation of 2,2-(ethylenedioxy)bis(ethylamine) and imidazole-2-carboxaldehyde in a 1:2 ratio, and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Cd(II) metal ions were synthesized in a 1:1 ratio. Various methods were used to identify the Schiff base ligand and complexes. Characterization techniques such as infrared, UV, and 1H NMR spectral tests, elemental analysis, molar conductivity, magnetic properties, thermal analysis, BET surface area, and theoretically by DFT were used to help further understanding of the complex structures. For all complexes, the ligand behaved as a neutral tetradentate ligand with NOON donor atoms and spectroscopic studies indicated an octahedral structure. The electrolytic behavior of the complexes was revealed by the molar conductivity measurements. In addition, thermogravimetric analysis was used to investigate the decomposition of the complexes and Schiff base ligand. According to the results obtained, the antibacterial activity of the metal complexes is higher than that of the Schiff base ligand against one or more bacterial species. The results showed that Cd(II) complex exhibits enhanced activity against Aspergillus flavus and Ni(II) complex against Candida albicans than the standard drug ketoconazole. The Mn(II) complex had stronger activity against human breast cancer cell line (MCF-7) than the other complexes. Antiviral drug development is critical in the latest outbreak of a novel coronavirus (SARS-CoV-2). The new coronavirus was screened using molecular docking. [ABSTRACT FROM AUTHOR]

This work investigates in depth the thermal degradation process of a polymer of urethane dimethacrylate (UDMA). UDMA monomer has been widely used in dental restorations and biomaterials. The use of density functional theory (DFT) calculations provided the bases for understanding the structure and reactivity of the UDMA monomer. Simultaneous thermogravimetry–differential thermal analysis, Photovisual Differential Scanning Calorimetry, and mid-infrared spectroscopy (MIR) were used to examine the depolymerization and degradation process. Non-isothermal kinetics made it possible to determine the best fit (n-dimensional nucleation according to Avrami–Erofeev followed by two competitive processes: nth order with autocatalysis by-product and reaction of nth order). Furthermore, the UDMA-P lifetime (5%) was calculated to show a degradation time of 3 years at 100.0 °C. Notwithstanding, techniques such as MIR and nuclear magnetic resonance 13C, 1H linked to DFT calculations helped to elucidate the cleavage positions and possible degradation by-products of UDMA degradation. [ABSTRACT FROM AUTHOR]

Mononuclear chelates of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Cd(II) resulted from new tridentate Schiff base ligand, 4‐((1‐(5‐acetyl‐2,4‐dihydroxyphenyl)ethylidene)amino)‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one, were synthesized. Metal to ligand ratio was found to be1 : 1, which was revealed via elemental analysis and characterized via various spectroscopic tools. IR has point out that the coordination of the ligand towards the metal ions was carried out via NOO donor atoms. UV‐Vis, 1H NMR spectral data, molar conductivity measurements, BET surface area, melting points and theoretically through density function theory were used such as characterizing techniques in supporting further interpretation of the complexes structures. The complexes were octahedral except Cu(II) and Ni(II) complexes were tetrahedral as suggested from the magnetic moment measurement. The complexes were found to have surface area, pore volume and particle radius of 23–176 m2 g−1, 0.02‐0.33 cc/g and 8.71‐4.32 nm, respectively, as pointed out from BET measurement. Schiff base ligand and metal complexes were tested in vitro to estimate their antimicrobial activity opposed to Gram‐negative and Gram‐positive bacterial and fungal organisms. MOE 2008 was used headed for screen potential drugs with molecular docking by the protein sites of new coronavirus and the study was constructed to molecular docking without validation through MD simulations. [ABSTRACT FROM AUTHOR]

In this study, investigation on the essential oils and ethanol extracts of naturally grown and cultivated Satureja macrantha samples were reported. The essential oil, flavour and terpenoid-steroid-flavonoid contents of S. macrantha samples were determined by GC-MS and their phenolic contents by LC-MS/MS. Besides, the biological activities of the samples were investigated for their antioxidant, anti-Alzheimer, antimicrobial, cytotoxic, antityrosinase, antiurease, antielastase and anticollagenase properties. The phenolic content and antioxidant capacity of the cultivated sample were higher than those of the naturally grown sample. According to the GC-MS results, terpinene-4-ol (30.9%) and p-cymene (56.7%) were determined as the major components in the essential oils of the naturally grown and cultivated S. macrantha, respectively. The flavour analysis results showed that cis-sabinene hydrate (20.7%) and carvacrol (42.2%) were found to be the major components in the naturally grown and cultivated samples, respectively. While the naturally grown sample was rich in abietane diterpenoids (ferruginol (17.5 mg analyte/g extract) and sugiol (4.2 mg analyte/g extract)), these components were not detected in the cultivated sample. The rosmarinic acid content (0.20 and 24.87 mg analyte/g extract, respectively) of the cultivated sample was found to be significantly higher than that of the natural sample. The biological activities of the samples were determined to be changed in parallel with their chemical contents that are due to factors such as climatic conditions, and soil structure. [ABSTRACT FROM AUTHOR]

A new streptovaricin analogue, namely 3-desmethyl protostreptovaricin I (1), was isolated from the culture of the genetically engineered strain ΔstvM2 derived from Streptomyces spectabilis CCTCC M2017417. Its structure was elucidated on the basis of extensive spectroscopic analyses, including 1D and 2D NMR tests, and high resolution mass spectrometry analysis. Compound 1 is the first example of 3-desmethyl streptovaricin analogues reported so far, however, it showed no antibacterial activities against Staphylococcus aureus ATCC 29213. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two undescribed secondary metabolites were isolated from endophytic fungus Stagonosporopsis oculihominis. • (±)-Stagonosporopsin A is a pair of enantiomer. • Stagonosporopsin C exhibited moderate inhibitory activity against Staphylococcus aureus subsp. aureus ATCC29213. A successive investigation of the endophytic fungus Stagonosporopsis oculihominis isolated from Dendrobium huoshanense led to the discovery of two undescribed secondary metabolites, (±)-stagonosporopsin A and stagonosporopsin B, and a new natural product, stagonosporopsin C. (±)-stagonosporopsin A is a pair of enantiomer. The structures of the isolated compounds, including their absolute configurations, were elucidated based on extensive spectroscopic analyses, electronic circular dichroism (ECD) calculations and X -ray diffraction. Stagonosporopsin C exhibited moderate inhibitory activity against Staphylococcus aureus subsp. aureus ATCC29213 with an MIC 50 value of 41.3 μ M. [ABSTRACT FROM AUTHOR]

The hexane and ethanol extracts from Himatanthus bracteatus (Apocynaceae) stems were evaluated for antiviral activity against Zika virus, yellow fever virus and dengue virus 2 and for cytotoxicity in Vero cells by MTT assay. The ethanol extract showed good antiviral activity against the three viruses with selective indexes (SI) > 10 and its fractionation led to the isolation of the known plumieride that was active only against Zika virus (SI of 15.97). [ABSTRACT FROM AUTHOR]

Strong and weak interactions between ionic liquids and dyes have been studied. The study has been tested with the removal of methylene blue from wastewater by1-butyl-1-pyrrolidinium hexafluorophosphate. The attractive interaction between Ionic Liquid (IL) 1-butyl-1-methyl pyrrolidinium hexafluorophosphate [bmpyr] and Methylene Blue (MB) has been investigated using electric conductivity measurements. The formation of associates between the IL anion (PF6-) and cationic MB has been made in evidence by means of spectroscopic analyses namely Ultra-Violet Visible (UV-Vis), Fourier Transform Infra-Red (FTIR) and Nuclera Magnetic Resonance (NMR). The results have been compared to previous data of 1-butyl-3- methylimidazolium hexafluorophosphate [bmim]. Having the same carbon chain, this latter gives associate constants which are higher than those of the former IL[bmpyr], suggesting the induced strong interaction between both species. In effect, the envelope of electron density of ILbmim, caused by nitrogen N1 inside the cycle, increases greatly the interaction. Really, this phenomenon might be attributed to complex formation readily affected by the conjugated diene system and the presence of a low pair of electrons provided by the tertiary at N1 of [bmim] compound. Besides, the symmetrical singly charged Cl- and PF6- anions being structure breaker and borderline structure breaker respectively, determined the type of interaction that may occur between the IL and MB. The results suggest also the strongest interaction between the inorganic anion PF6- of IL and organic cation of MB leading to its reduction. At last, it has been proved through this fundamental study that IL [bmpyr] is not efficient enough to remove MB compared to other suitable ILs. It may nevertheless be good enough to detect traces of dyes in very dilute solutions. [ABSTRACT FROM AUTHOR]

Cueva de Ardales in Málaga, Spain, is one of the richest and best-preserved Paleolithic painted caves of southwestern Europe, containing over a thousand graphic representations. Here, we study the red pigment in panel II.A.3 of "Sala de las Estrellas," dated by U-Th to the Middle Paleolithic, to determine its composition, verify its anthropogenic nature, infer the associated behaviors, and discuss their implications. Using optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction, we analyzed a set of samples from the panel and compared them to natural coloring materials collected from the floor and walls of the cave. The conspicuously different texture and composition of the geological samples indicates that the pigments used in the paintings do not come from the outcrops of colorant material known in the cave. We confirm that the paintings are not the result of natural processes and show that the composition of the paint is consistent with the artistic activity being recurrent. Our results strengthen the hypothesis that Neanderthals symbolically used these paintings and the large stalagmitic dome harboring them over an extended time span. [ABSTRACT FROM AUTHOR]

• We investigated mural paintings covering 60 years of street art history. • μ-Raman and ED-XRF were used to characterize the organic and inorganic pigments. • HPLC-MS and HPLC-DAD were used to complement the characterization of organic pigments. • Py-GC/MS was used to study characterize the paint binders and additives. • We compared our results with the literature to draw a timeline of the materials. Street art murals are an artistic expression strictly interwoven in the urban landscape, and in recent years have received increasing attention as cultural heritage at risk. Today there is intense debate regarding the value assessment and choices related to the conservation of urban art; however, the evaluation of the stability of modern paint materials in outdoor environment is preliminary to any possible preservation strategy. In particular, the identification of the materials constituting a street artwork is critical for the preservation of these non-permanent heritage elements and to define the best restoration approaches. In this work, we performed a set of analyses of microsamples based on spectroscopy, analytical pyrolysis, gas and liquid chromatography, and mass spectrometry to identify paint materials (binders, pigments, additives, degradation products and conservation/restoration materials) of a selection of mural paintings, covering 60 years of history (1953–2014). The goal of this work was to identify the materials used to produce different mural paintings and to relate and compare their different compositions with previous studies in order to describe the evolution of the materials during the last 60 years. The collected knowledge and the limited data available in literature were exploited to increase the scientific background on the materials used by street artists, and to fill the lack of knowledge on this emerging topic. [ABSTRACT FROM AUTHOR]

Three-dimensional chitosan-gallic acid complexes were proposed and prepared for the first time by a simple adsorption process of gallic acid (GA) on three-dimensional chitosan structures (3D chitosan). Highly porous 3D devices facilitate a high GA load, up to 2015 mmol/kg at pH 4.0. The preservation of the redox state of GA released from 3D chitosan was confirmed by spectroscopic analyses. The antioxidant activity of 3D chitosan-GA complexes was assessed using the DPPH radical scavenging assay and was found to be dramatically higher than that of free chitosan. The mechanical property of 3D chitosan–GA complexes was also evaluated using a compression test. Finally, 3D chitosan–GA complexes showed a significant antimicrobial capacity against E. coli and S. aureus, selected, respectively, as a model strain for Gram-negative and Gram-positive bacteria. Our study demonstrated a new, simple, and eco-friendly approach to prepare functional chitosan-based complexes for nutraceutical, cosmeceutical, and pharmaceutical applications.

Pleurotus ostreatus (Jacq. :Pers.) Roll is a grey edible mushroom (Agaricochaete), containing a variety of vitamins, minerals and different kind of secondary metabolites. Two new terpenoid indole alkaloids (Terpendole N and Terpendole O) were isolated from the fermentation of P. ostreatus. Their structures were elucidated by 1D, 2D NMR, HR-ESI-MS, and ECD. [ABSTRACT FROM AUTHOR]

HL1 and HL2 (HL1 = 5-diethylamino-2-({[4-(diethylamino)phenyl]imino}methyl)-phenol; HL2 = 5-diethylamino-2-({[4-(dimethylamino)phenyl]imino}methyl)-phenol) are new Schiff base ligands which were prepared along with their metal(II) complexes of [Cu(L1)2] (1), [Cu(L1)2] (2), [Ni(L2)2] (3) and [Ni(L2)2] (4) and characterized by different analytical as well as spectroscopic analyses. The single crystal XRD analysis confirms the proposed structure of ligands such as HL1 and HL2. EPR spectral analysis gives evidence about the tetrahedrally coordinated geometry of complexes 1 and 2. Density functional theory (DFT) analysis was executed using B3LYP/6-31G(d,p)∪LanL2DZ level. The DNA sequence (along with Dickerson's sequence) specificity of complexes 1–4 was evaluated and it has resulted that the complexes 1–4 primarily interact with double helix of DNA via groove mode of binding. From plasma protein docking results, we can say that complexes 2 and 4 showed more binding towards HSA and may have good bioavailability and are prone to act as drug candidates. The observed findings show that these metal(II) complexes 1–4 are better DNA probes, will act as anticancer agents and stimulate strong research focusing on the design of new chemical probes of DNA. [ABSTRACT FROM AUTHOR]

Two new 2(1H)-pyrazinone derivatives, 3,6-diisopropyl-5-methylpyrazin-2(1H)-one (1) and 5- (hydroxymethyl)-3,6-diisopropylpyrazin-2(1H)-one (2), were isolated from the fermentation broth of endophytic actinomycete Streptomyces sp. KIB-H1992. Their structures were established based on the detailed spectroscopic analyses, including ESI-MS, HR-ESI-MS, 1D and 2D NMR spectra. [ABSTRACT FROM AUTHOR]

The effect of concentration and origin of dissolved organic matter (DOM) on acenaphthene (Ace) photodegradation in liquid water and ice was investigated, and the components in DOM which were involved in Ace photodegradation were identified. The DOM samples included Suwannee River fulvic acid (SRFA), Elliott soil humic acid (ESHA), and an effluent organic matter (EfOM) sample. Due to the production of hydroxyl radical (•OH) and triplet excited-state DOM (3DOM*) which react with Ace, DOM had promotion effects on Ace photodegradation. However, the promotion effects of DOM were prevailed over by their suppressing effect of DOM including screening light effect, intermediates reducing effect and RS quenching effect, and thus, the photodegradation rates of Ace decreased in the presence of the three DOM with concentrations of 0.5–7.5 mg C/L in liquid water and ice. ESHA had higher light absorption and thus had higher screening light effect on Ace photodegradation in liquid water than SRFA and EfOM. At each DOM concentration, ESHA exhibited higher promotion effect on Ace photodegradation than SRFA and EfOM, in liquid water and ice. The binding of Ace with DOM was indicated by decreases in fluorescence intensity of Ace when coexisted with DOM. However, the binding of Ace to DOM played an unimportant role in suppressing Ace photodegradation. The photodegradation behavior of fluorophores in Ace with DOM present in ice was not similar to that in liquid water. C–O, C═O, carboxyl groups O–H and aliphatic C–H functional groups in DOM were involved in the interaction of DOM with Ace. The presence of Ace seemed to have no influence on the photodegradation behavior of functional groups in DOM. [Display omitted] • Direct photolysis kinetics of Ace were similar in liquid water and ice. •0.5–7.5 mg C/L DOM exhibited suppressing effect on Ace photodegradation. •.•OH and 3DOM* generated form DOM played important roles in Ace photodegradation •Production of functional groups from direct Ace photolysis was different in water and ice. •Photodegradation of fluorophores in Ace with DOM present was different in water and ice. [ABSTRACT FROM AUTHOR]

Persimmon tannins, particularly in immature persimmons, haven't yet received corresponding attention to research on therapy of diabetes mellitus in spite of high hypoglycemic activity. To accurately screening key hypoglycemic components, immature persimmon extracts were isolated and identified using enzyme affinity ultrafiltration and HRLC-ESI-MS/MS. Among them, Hederagenin (IC 50 = 0.077 ± 0.003 mg/mL), Ursolic acid (IC 50 = 0.001 ± 0.000 mg/mL) and Quercetin dehydrate (IC 50 = 0.081 ± 0.001 mg/mL) exhibited the strongest inhibitory effect on α-amylase (HSA and PPA) and α-glucosidase, respectively. And their inhibition mechanisms were analyzed using multi-spectral analysis, atomic force microscope and molecular docking, indicating the bonding with starch digestion enzymes through hydrogen bonding and hydrophobic interaction, and generating the enzyme aggregation. In vivo starch-tolerance experiment further verified that these inhibitors could improve postprandial hyperglycemia (17.18 % ∼ 40.29 %), far more than acarbose. Suppressing, Hederagenin and Ursolic acid as triterpenoids appeared amazing potentiality to alleviate postprandial hyperglycemia, which suggested that IPE were comprehensive exploration values on prevention and treatment of hyperglycemia. • Immature persimmon extracts (IPE) exhibited inhibition for starch digestive enzymes. • Hederagenin, ursolic acid and quercetin dihydrate were the main inhibitors in IPE. • IPE inhibited starch digestive enzymes via H-bonding and hydrophobic interaction. • High hypoglycemic activity of IPE resulted from inhibiting starch digestive enzymes. • Ursolic acid as triterpenoids appeared the strongest hypoglycemic activity. [ABSTRACT FROM AUTHOR]

The usefulness of the structure of galloyl hydrazide (3,4,5-trihydroxybenzohydrazide, coded as 2nz in this article) as a privileged structural system in pharmaceutical organic and medicinal chemistry has prompted the advances of the further therapeutic potentials of this known antioxidant/antitumor compound and, in addition to that, it acts generally as a very important organic reaction intermediate for molecule planning (including synthesis of many important biologically active molecules), as it undergoes various types of chemical reactions. The data of the two synthetic methods (including the new green one), presented in this research article, provides sharp adequate chemical data about the challenging synthesis, separation (purification), and characterization of this compound. A new and very fast one-pot solventless greener microwave-assisted method of synthesis, in addition to the much slower old conventional one, is used in this present research; and followed by full precise purification and characterization (including chromatographic separation; physicochemical identification; IR, 1H-NMR, 13C-NMR, and mass spectroscopic analyses along with elemental analyses for structure elucidation) of 2nz. • Galloyl hydrazide is a very important and unique organic chemical intermediate with, mainly, antioxidant and anticancer biological activities. • Galloyl hydrazide synthesis in the previous literature is very challenging, confusing, not standardized, and without any consensus. • The main objective of this new research is to make two standard and fixed methods of synthesis (conventional and greener) of galloyl hydrazide through designing and constructing a new one-pot solventless greener microwave-assisted synthetic method, in addition to redesigning and qualifying the old traditional conventional heating one; both methods are followed by very accurate identification and characterization data (which can be referenced for the efficient reproducibility in the organic and pharmaceutical chemistry community) of galloyl hydrazide.

In this work, the preparation of new multidentate Schiff-base lig and and its metal complexes are described. The formation of the lig and{ 2,2'((5-methyl-1,3-phenylene)-bis-(oxy))-bis-N'(E')-2-hydroxybenzylideneacetohydrazide}[H2L] was prepared from the reaction {2,2-((5-methyl-1,3-phenylene)-bis-(oxy))-di-(acetohydrazide)}[M]precursor and salicylaldehyde in a 1:2 mole ratio, respectively. The reaction of the lig and [H2L] with (Cr+3, Mn+2 and Fe+2)metal ions in a 1:2 (L:M) mole ratio. Ligand and complexes were characterised via spectroscopic analyses; [FT-IR, UV-Vis spectroscopy,(C.H.N) microanalysis, chloride content, thermal analysis(TG), electrospray mass, magnetic susceptibility and conductivity measurements. The characterisation data showed the six coordinate complexes with the general formula;[M2(L)Cl4] (where M= Cr+3) and K2[M2(L)Cl4] (where M= Mn+2 and Fe+2). The ligand [H2L] and its complexes were screened for their antimicrobial activity against four bacterial species (Bacillus subtitles and Staphylococcus aureus) G-positive, (Escherichia coli and Pseudomonas aeruginosa) G-negative and two fungi species(Candida and trichomoniasis). Biological data indicated that complexes become potentially more active against several type of organism, under survey compared with the free lig and. [ABSTRACT FROM AUTHOR]

Abstract The darkening process of cinnabar and vermilion-based paint surfaces as well as pigment-binder interactions upon weathering have been studied by subjecting egg-yolk tempera dosimeters to UV-aging, RH cycling, and 2-year outdoor weathering with and without direct exposure to rain and sunlight. X-ray photoelectron spectroscopy proved that photooxidation resulted in Hg enrichment in the cinnabar pigment surface of weathered paints exposed to direct sunlight and rain, which caused important binder loss as well as thermal-induced crack formation and severe darkening of the unprotected pigments. Remarkably, darkening occurred in the absence of halogens and all pigments, independent of their preparation process (ground minerals or synthesis by a wet-process), were affected. After UV-aging, RH-cycling, and outdoor weathering in the absence of direct sunlight and rain, in contrast, pigments were still covered by egg yolk and did not undergo significant alteration. The binder, however, suffered important conformational and physical changes, including crack formation. These changes were significantly influenced by the size of the pigment. Additionally, XRD results indicate the presence of metacinnabar as an impurity in the original cinnabar and vermilion pigments, which might have been mistakenly identified as an alteration product in previous studies. Graphical abstract Unlabelled Image Highlights • Evidence of Hg-enrichment in cinnabar pigment surface upon light exposure • Darkening of cinnabar pigments in the absence of chlorides • Presence of metacinnabar in the original cinnabar pigments • Pigment particle size influences pigment-binder interaction and alteration. [ABSTRACT FROM AUTHOR]

Background: This study investigates the potential of eleven 1H-1,2,3-triazol-1,4-naphthoquinone conjugates as virulence factor inhibitors (like Pyocyanin) and their affinity for PhzM, a crucial enzyme for Pyocyanin biosynthesis in Pseudomonas aeruginosa infections., Methods: A straightforward synthetic pathway enabled the production of these compounds, which were characterized and structurally confirmed through spectroscopic analyses. Evaluation of their impact on PhzM thermal stability identified promising candidates for PhzM binders., Results: Concentration-response behavior elucidated their binding affinity, revealing them as the first reported micromolar affinity ligands for PhzM. Structure-activity relationship analysis emphasized the role of specific molecular moieties in binding affinity modulation, paving the way for future advanced inhibitors' development., Conclusion: These findings highlight the potential of naphthoquinone-triazole derivatives as leads for novel therapeutics against P. aeruginosa infections., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Four new steroids cynansteroid G-I ( 1-3 ) and cynansteroid K ( 4 ), a new natural product 5,6-deacidizingcaudatin ( 5 ), and a known compound glycocaudatin ( 6 ), were isolated from the roots of Cynanchum auriculatum . The structures of new compounds were identified by comprehensive spectroscopic analyses, including NMR, HRESI-MS, ECD, UV, and IR spectral data. The cytotoxic activities of all the isolates against two human tumour cell lines (COLO-205 and BGC-823) were screened, unfortunately, which were weaker than positive control.

One new havanensin-type limonoid (1) named trisinlin A with two known compounds (4E,8E)-2-[2′-hydroxyhexadecanoyl amino]-4,8-octadecadiene-1,3-diol (2), 9-octadecenoic acid-2′,3′-dihydroxypropyl ester (3) were isolated from the roots of Trichilia sinensis. The structure of the new compound was unambiguously determined through comprehensive spectroscopic analyses including 1D and 2D NMR, and mass spectrometry, as well as by comparison with the literature. Trisinlin A showed significant insecticidal activity against newly hatched larvae of Spodoptera litura. [ABSTRACT FROM AUTHOR]

Abstract In the present study, the macroscopic sorption behaviors and microscopic immobilization mechanisms of Ni(II) at cryptomelane/water interfaces were explored using the combination of batch sorption technique, desorption procedure, theoretical simulation, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) analyses. The good simulation of the pseudo-second-order model on the sorption kinetics data suggests a driving force of chemical sorption rather than mass transport or physical interaction. The sorption trends and uptake mechanisms are obviously related to the solution pH, with cation exchange or outer-sphere surface complexation at an acidic pH of 4.0, inner-sphere surface complexation in both the edge-shared (ES) and double corner-shared (DCS) modes at a neutral pH of 7.0, and precipitation of α-Ni(OH) 2 (s) phase at a highly alkaline pH of 10.0. The gradual increase of Ni(II) sorption amount with solution temperature rising from 293 K to 333 K is consistent with the increased ratio of the weak DCS configuration. The research findings herein can help us better understand the migration and transformation trends of Ni(II) in the manganese mineral-riched aquatic environment. Graphical abstract Image 1 Highlights • Interaction mechanisms of Ni(II) with cryptomelane were explored by combining multiple techniques. • Relative contributions of different uptake processes were verified from ligand extraction data. • Ni(II) binding modes were clearly identified with theoretical simulation and spectroscopic analyses. • Temperature rising enhanced the sorption amount of Ni(II) in double corner-shared binding mode. • Research findings facilitated the assessment of Ni(II) migration and fate in Mn-riched environment. [ABSTRACT FROM AUTHOR]

The new chalcone compound namely (E)-1-(4-Bromophenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one (C18H17BrO4) is crystallized in the monoclinic crystal system of P21/c space group. The unit cell dimensions are: a = 8.0753 (10) Å, b = 21.873 (3) Å, c = 9.3362 (12) Å, α = 90°, β = 99.369 (2), γ = 90° and Z = 4. The single crystal was grown using slow evaporation solution growth technique. The newly synthesized compound was characterized by using IR, 1H- and 13C-NMR, UV-Vis and single crystal X-ray diffraction analyses. Quantum chemical method of Density Functional Theory (DFT) with B3LYP/6-311++G(d,p) has been employed to study the structural and spectral properties of the compound. The electronic absorption spectrum was calculated using the time dependent functional theory (TDDFT) method. The most stable conformer of the title chalcone is identified from the computational results. Hirshfeld surface analysis with fingerprint plots has been used as a graphical tool for visualization and understanding of intermolecular interactions. Intermolecular C-H····O interaction observed stabilize the crystal structure, forming an infinite one dimensional column. The effect of this intermolecular interaction in the solid state can be seen in the difference between the experimental and the theoretically optimized geometrical parameters. The crystal is transparent in the entire visible region and absorptive in the UV region. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron potential (MEP). The other molecular properties like charge transfer are explain using Mulliken population analysis. The antioxidant test indicated that the 2,3,4-trimethoxy substitution on the bromide chalcone to be one of the favorable modification to enhance its metal chelating activity. [ABSTRACT FROM AUTHOR]

The materials used in the historical restoration of a fossil collection named “Problematica Verrucana”, have been studied in order to contribute to the creation of a catalogue of restoration materials used in the past. Due to the complexity of the mixtures used with different purposes to restore fossil finds, an extractive technique has been employed in order to separate the compounds soluble in solvents with different polarities. Using this procedure several components, even when found in small amounts, have been identified. The chemical composition of the organic and inorganic compounds used in the restoration material has been determined using extractive procedure, FT-IR and 1H-NMR spectroscopies. A preliminary macroscopic characterisation and mineralogical and petrographical analyses have also been performed on the inorganic filling materials found in several samples. The different compositions of various materials used in the restoration of this fossil collection might be related to the particular conservative and esthetic functions of the product applied on the find.

Three new isomalabaricane-type terpenoids, jaspiferins H (1), I (2), and J (3), were isolated from the marine sponge Jaspis stellifera collected from the South China Sea. The structures of the new metabolites were elucidated on the basis of extensive spectroscopic methods. [ABSTRACT FROM AUTHOR]

ABSTRACT A tricomponent system, constituting monomer (methyl methacrylate, MMA), higher oxidation state transition-metal catalyst (FeBr3) and a ligand (triphenylphosphine, PPh3), MMA/FeBr3/PPh3 system without external initiator (alkyl halide) has been studied extensively with different spectroscopic analyses. To figure out the mechanism, a series of explicit model reactions were conducted with a molar ratio of [MMA]0/[FeBr3]0/[PPh3]0 = 200/1/ n ( n = 0.1-3.0) at 80 °C, and the corresponding polymerization behaviors were investigated. Combined with theoretical deduction and spectroscopic evidences, the composition of the in-situ generated initiators was gradually confirmed, which were redox products of FeBr3 and PPh3. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3842-3850 [ABSTRACT FROM AUTHOR]

Two new malic acid derivatives, namely eucomic acid 1-methyl ester (2) and 6′′′-acetylmilitaline (7), together with ten known compounds (1,3–6,8–12), were isolated from the dry tubers ofBletilla striata(Thunb.) Reichb. F., a perennial traditional Chinese medicinal herb, which was used for the treatment of pneumonophthisis, pneumonorrhagia, tuberculosis, and hemorrhage of the stomach or lung. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS. [ABSTRACT FROM AUTHOR]

Effective interaction of natural alkaloid Luotonin A ( L ) and its affixed acceptor molecules 1 and 2 with donor molecule as Bovine serum albumin (BSA) at various pH (4.0, 7.4 and 10.0) medium have been demonstrated using various conventional spectroscopic techniques. These analyses provide some valuable features on the interaction between BSA and acceptor molecules ( L , 1 and 2 ). From the absorption and fluorescence spectral titration studies, the formation of ground-state complexes between the acceptor molecules ( L , 1 and 2 ) and the BSA have been confirmed. The results of the afore titrations analysis reveal that, the strong binding of receptor 1 with BSA ( K app 5.68 × 10 4 M − 1 ; K SV 1.86 × 10 6 L mol − 1 ; K a 6.42 × 10 5 L mol − 1 ; K ass 8.09 × 10 6 M − 1 ; ΔG − 33.35 kJ/mol) at physiological pH medium (7.4) than other receptor molecules 2 and L . The Förster resonance energy transfer (FRET) efficiency between the tryptophan (Trp) residues of BSA and acceptor molecules L , 1 and 2 during the interaction, are 28.85, 85.24 and 53.25 % respectively. The superior binding efficacy of acceptor 1 at physiological pH condition has been further confirmed by FT-IR and Raman spectral analysis methods. Moreover, theoretical docking studies of acceptors L , 1 and 2 towards HSA have been demonstrated to differentiate their binding behaviours. It reveals that, acceptor 1 has the strongest binding ability with HSA through two hydrogen bonding and the Atomic contact energy (ACE) value of − 483.96 kcal/mol. [ABSTRACT FROM AUTHOR]

The condensation of o-benzoyl benzoic acid and 4-aminoantipyrine resulted in the formation of novel Schiff base ligand (HL) with the IUPAC name 2-(((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1 H-pyrazol-4-yl)imino)(phenyl)methyl)benzoic acid. The synthesized Schiff base ligand and its complexes with M(II)/(III) transition elements (Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)) were characterized by elemental, magnetic susceptibility, molar conductivity, spectroscopic (H NMR, mass, UV-visible, FTIR, ESR), thermal and X-ray powder diffraction. The data showed that the complexes had composition of the MHL type. The diffused reflectance spectra, magnetic susceptibility and ESR spectral data of the complexes confirm an octahedral geometry around metal ions. The thermal analysis data revealed the decomposition of the complexes in three to five successive decomposition steps within the temperature range of 30-1000°C, and the activation thermodynamic parameters were reported. The molecular structures of the Schiff base ligand and its Mn(II) and Zn(II) metal complexes are optimized theoretically, and the quantum chemical parameters are calculated. In order to predict the binding between o-benzoyl benzoic acid, 4-aminoantipyrine and HL ligand with the Escherichia coli bacterial RNA (4p20) receptor, molecular docking was carried out. The in vitro antimicrobial screening of the newly synthesized compounds was tested against different bacterial and fungal organisms. The results showed that the metal complexes have biologically activity more than the new Schiff base ligand against the tested organisms. The Schiff base ligand and its complexes were also screened for their anticancer activity against breast cancer cell line (MCF7). The Mn(II), Cr(III) and Cd(II) complexes were found to have low IC values which support the possibility of using them as cytotoxic agents and hence might become good anticancer agent in clinical trials. [ABSTRACT FROM AUTHOR]