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Panax notoginseng saponins (PNS) are the main active components of Panax notoginseng. But after oral administration, they need to be converted into rare ginsenosides by human gut microbiota and gastric juice before they can be readily absorbed into the bloodstream and exert their effects. The sources of rare ginsenosides are extremely limited in P. notoginseng and other medical plants, which hinders their application in functional foods and drugs. Therefore, the production of rare ginsenosides by the transformation of PNS using Aspergillus fumigatus was studied in this research. During 50 days at 25 ℃ and 150 rpm, A. fumigatus transformed PNS to 14 products (1–14). They were isolated by varied chromatographic methods, such as silica gel column chromatography, Rp-C18 reversed phase column chromatography, semi-preparative HPLC, Sephadex LH-20 gel column chromatography, and elucidated on the basis of their 1H-NMR, 13C-NMR and ESIMS spectroscopic data. Then, the transformed products (1–14) were isolated and identified as Rk3, Rh4, 20 (R)-Rh1, 20 (S)-Protopanaxatriol, C-K, 20 (R)-Rg3, 20 (S)-Rg3, 20 (S)-Rg2, 20 (R)-R2, Rk1, Rg5, 20 (S)-R2, 20 (R)-Rg2, and 20 (S)-I, respectively. In addition, all transformed products (1–14) were tested for their antimicrobial activity. Among them, compounds 5 (C-K) and 7 [20 (S)-Rg3] showed moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 6.25, 1.25 μg/mL and 1.25, 25 μg/mL, respectively. This study lays the foundation for production of rare ginsenosides. [ABSTRACT FROM AUTHOR]

In order to improve and replace the enantiomer method outlined in the olodaterol hydrochloride draft monograph (From the European Pharmacopoeia forum), one new, simple, and fast enantioselective normal phase high‐performance liquid chromatography chiral method was developed on polysaccharide‐based Chiral MX (2) (4.6 × 250 mm, 5 μm) column. n‐Hexane, ethanol, and diethylamine in the ratio of 40:60:0.1 (V/V/V) were selected as mobile phase at a flow rate of 0.8 mL/min, and the detection was performed on a photodiode array detector at 225 nm with 5 μL injection volume. The column temperature was set at 40°C for better peak shape and sensitivity. The analysis time can be shortened to 15 min, whereas the resolution between enantiomer and olodaterol was found to be even more than 10.0, which was far better than that obtained with the reported method in this draft monograph. The developed chiral method was validated in accordance with ICH Q2 (R1), including specificity, LOD&LOQ, precision, linearity, accuracy, and robustness. Thereby, the proposed method was demonstrated to be suitable for the determination of enantiomer in olodaterol hydrochloride bulk drug and drug product. Besides, the thermodynamic parameters were evaluated on the basis of Van't Hoff plots that was used to explain correlative chiral recognition mechanisms with the chiral stationary phase. [ABSTRACT FROM AUTHOR]

A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all‐alkynyl‐protected gold nanoclusters. Direct reduction of dpa‐passivated precursor Au‐dpa (Hdpa=2,2'‐dipyridylamine) in one‐pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R=−C6H4−2−F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40 % (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO‐LUMO gap than Au130(S−C6H4−4−CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all‐alkynyl‐protected gold nanoclusters. [ABSTRACT FROM AUTHOR]

A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all‐alkynyl‐protected gold nanoclusters. Direct reduction of dpa‐passivated precursor Au‐dpa (Hdpa=2,2'‐dipyridylamine) in one‐pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R=−C6H4−2−F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40 % (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO‐LUMO gap than Au130(S−C6H4−4−CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all‐alkynyl‐protected gold nanoclusters. [ABSTRACT FROM AUTHOR]

Although helicenes are promising molecules, the synthetic difficulty and tediousness have often been problems, and only small amounts of optically pure helicenes have been obtained by using chiral HPLC in most cases. Herein, aza[7]helicenes or closed‐aza[7]helicenes with (1R)‐menthyl substituents were selectively synthesized via the intramolecular Scholl reaction, and the diastereomeric pairs were separated by silica gel column chromatography. The optically pure helicenes were further transformed into the corresponding cyclic dimers, and the chiroptical properties were investigated. The rigid π‐frameworks of the dimers led to the high molar extinction coefficients and fluorescence quantum yields, while the twisted helicene moieties induced clear Cotton effects and CPL in the visible region, and the high CPL brightness (BCPL) was achieved. Furthermore, the cyclic dimers were found to have the macrocyclic cavity with the two NH groups suitable for the selective binding of a fluoride anion, which induced significantly redshifted fluorescence and CPL in the red region. [ABSTRACT FROM AUTHOR]

AbstractMass spectrometry (MS) enables precise identification and quantification of molecules, particularly when combined with chromatography. The advent of atmospheric pressure ionization (API) techniques allowed the efficient coupling of liquid chromatography with MS (LC-MS), extending analyses to nonvolatile and thermolabile compounds. API techniques present limitations such as low informative capacity and reproducibility of mass spectra, increasing instrument complexity and costs. Other challenges include analyzing poorly polar molecules and matrix effects (ME), which negatively impact quantitative analyses, necessitating extensive sample purification or using expensive labeled standards. These limitations prompted the exploration of alternative solutions, leading to the development of the Liquid Electron Ionization (LEI) interface. The system has demonstrated excellent robustness and reproducibility. LEI has been employed to analyze various compounds, including pesticides, drugs of abuse, phenols, polycyclic aromatic hydrocarbons (PAHs), phthalates, and many others. Its versatility has been validated with single quadrupole, triple quadrupole, and QToF detectors, operating in electron ionization (EI) or chemical ionization (CI) modes and with both reverse phase liquid chromatography (RPLC) and normal phase liquid chromatography (NPLC). LEI has also been successfully integrated with the Microfluidic Open Interface (MOI), Membrane Introduction Mass Spectrometry (MIMS), and Microfluidic Water-Assisted Trap Focusing (M-WATF), broadening its application scope and consistently demonstrating promising results in terms of sensitivity and identification power. The most recent advancement is the development of Extractive-Liquid Sampling Electron Ionization-Mass Spectrometry (E-LEI-MS), a surface sampling and real-time analysis technique based on the LEI concept. This review article offers a comprehensive and up-to-date picture of the potential of LEI. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis of the dopamine agonist Rotigotine, which is used to treat Parkinson's disease and restless leg syndrome. The authors discuss different synthetic approaches and successfully synthesized Rotigotine using reductive amination with a high yield. The document also includes information on the synthesis and characterization of three compounds related to Rotigotine, along with their spectral data. Additionally, it provides details on the synthesis and chiral separation of (±)-Rotigotine, including its chemical structure, physical properties, and analytical data. The authors acknowledge Chemveda Life Sciences for their assistance in the separation process. [Extracted from the article]

Camellia fascicularis has important ornamental, medicinal, and food values, which also have tremendous potential for exploiting bioactivities. We performed the bioactivity-guided (antioxidant and antimicrobial) screening of eight fractions obtained from the ethyl acetate phase of C. fascicularis. The antioxidant activity was measured by DPPH, ABTS, and FRAP, and the antibacterial activity was measured by the minimum inhibitory concentration (MIC) of Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. The results of bioactivity-guided isolation indicated that the major antioxidant compounds in the ethanolic extracts of C. fascicularis may be present in fractions (Fr.) (A–G, obtained after silica gel column chromatography). Fr. (D–I, obtained after silica gel column chromatography) is a fraction of C. fascicularis with antimicrobial activity. The structures of compounds were determined by spectral analysis and nuclear magnetic resonance (NMR) combined with the available literature on secondary metabolites of C. fascicularis leaves. In this study, 17 compounds were identified, including four phenolics (1, 3–4, and 14), a phenylpropane (2), five terpenoids (5–7, 12, and 15), four flavonoids and flavonoid glycosides (8–10 and 16), and two lignins (13 and 17). Compounds 4–7, 13–15, and 17 were isolated from the genus Camellia for first time. The remaining compounds were also isolated from C. fascicularis for first time. The evaluation of antioxidant and antimicrobial activities revealed that compounds 1, 3, 9, 11, and 17 exhibited higher antioxidant activity than the positive control drug (ascorbic acid), and compounds 4, 8, 10, and 13 showed similar activity to ascorbic acid. The other compounds had weaker or no significant antioxidant activities. The MIC of antibacterial activity for compounds 4, 7, and 11–13 against P. aeruginosa was comparable to that of the positive control drug tetracycline at 125 µg/mL, and other secondary metabolites inhibited E. coli and S. aureus at 250–500 µg/mL. This is also the first report of antioxidant and antimicrobial activities of compounds 5–7, 13–15, and 17. The results of the study enriched the variety of secondary metabolites of C. fascicularis and laid the foundation for further research on the pharmacological efficacy and biological activity of this plant. [ABSTRACT FROM AUTHOR]

Summary: Durian fruit rinds (Durio zibethinus) have increasingly attracted scientific interest due to their potent bioactive metabolites. In the present study, a comprehensive approach combining chromatographic techniques and bioassays was employed to elucidate the phytochemical constituents present in durian fruit rinds and their corresponding bioactivities. The crude ethanolic extract (CEE) and its fractions obtained through silica gel column chromatography (F1, F2, F3, and F4) were qualitatively and quantitatively analysed for their flavonoid profiles using thin‐layer chromatography, high‐performance liquid chromatography (HPLC), and liquid chromatography/mass spectrometry (LC/MS). Among the tested samples, fraction F2 exhibited the highest total flavonoid content (179.55 mg QE/g DW). TLC and HPLC analyses showed the presence of quercetin in all tested samples, with its content ranking in the order of F2 > F3 > F1 > F4 > CEE. The fractions exhibited inhibitory effects on albumin denaturation, protease activity, lipoxygenase (LOX), heat‐induced haemolysis, and xanthine oxidase (XO), surpassing those of the crude extract. These observed bioactivities correlated with the distribution of flavonoids and quercetin content in the samples. LC/MS analysis further showed the presence of flavonoids‐chalcone, flavonols, terpenoids, stilbene glycosides, anthocyanins, phenolics, and amino acids in fraction F2. These results determine the phytochemical profiles, anti‐inflammatory, and anti‐XO activities of bioactive fraction obtained from durian fruit rinds. [ABSTRACT FROM AUTHOR]

The given text discusses a recent article in the journal Synthesis that explores the synthesis of tetrasubstituted olefins, which are important in drugs and organic materials. The article proposes a method for synthesizing fully substituted olefins with multiple aryl substituents using a weakly coordinating directing group. It provides details on the experimental procedure, optimization, substrate scope, and potential applications of the method. Additionally, the text provides information on the synthesis and characterization of various chemical compounds, including their physical properties and spectroscopic data. The authors of the article are researchers from China, and their work focuses on C-H bond functionalization reactions. This information can be valuable for researchers studying organic chemistry and synthesis methods. [Extracted from the article]

This article discusses the modular synthesis of conjugated aromatic boronate esters through radical xanthate addition. The researchers successfully synthesized xanthates with phenylboronate groups and demonstrated their potential for synthesizing boronate-containing conjugated aromatic compounds. The document provides detailed information about the synthesis and characterization of various compounds, including their chemical structures, spectroscopic data, and yields. It can be useful for researchers studying organic synthesis and compound characterization. [Extracted from the article]

This document provides a concise summary of an article discussing the synthesis and analysis of 5,7,8,10-tetraphenyl-1,14-dianilinotripyrrins. The study explores the structural changes and properties of these compounds in response to different environments and substituents. The article provides detailed information on the synthesis, structures, and spectroscopic analysis of the synthesized compounds. The findings suggest potential applications as near-infrared emitters and further research on the photophysical dynamics of tripyrrins is ongoing. The document also acknowledges funding support and provides access to additional supporting information online. [Extracted from the article]

This article discusses the synthesis of N-trifluoromethyl thiocarbamates and ureas from 3-aminopyridine-derived carbamates. The authors present a new method for the synthesis of these compounds using isothiocyanates and carbonyl electrophiles. The article describes the reaction conditions and substrate scope for this synthesis, and the authors anticipate that this protocol will have numerous applications in drug discovery. The document provides procedures for the synthesis of various sulfamides derived from 3-aminopyridine, as well as information on the synthesis and characterization of various compounds using general procedures and techniques such as NMR and HRMS. The text also includes specific examples of synthesized ureas, along with their corresponding NMR and HRMS data. The supporting information for the article is available online. [Extracted from the article]

This article explores the use of cyanophosphates as synthetic intermediates in the transformation of benzaldehydes into benzonitriles. The researchers found that certain benzaldehydes reacted with tetrabutylammonium azide to form aromatic nitriles, while ketone or aliphatic aldehyde cyanophosphates resulted in the formation of tetrabutylammonium ethyl phosphates. The study also investigated the effects of reaction conditions on the transformation process. The document provides detailed information on the synthesis and characterization of various cyano(phenyl)methyl diethyl phosphate compounds, including their isolation methods and spectroscopic data. Additionally, the document includes chemical data for other compounds, such as tetrabutylammonium 3-(tert-Butyldimethylsiloxy)-17-cyanoestra-1,3,5(10)-trien-17-yl Ethyl Phosphate and 3-nitrobenzonitrile, along with their synthesis and purification methods. The authors express gratitude to their colleagues for their support and assistance. [Extracted from the article]

This document provides information on the synthesis and characterization of various compounds, including β-aminonitriles, β-amino sulfones, and dimethyl aspartates. The compounds were synthesized using lanthanoid triflates Yb(OTf)3 and Tb(OTf)3 as catalysts and the reactions were optimized for yield. The document also includes spectroscopic data, such as melting points and NMR spectra, for the compounds. The data presented in the document match those previously reported in the literature. The document acknowledges the facilities used for the research and dedicates the work to the late Prof. Ibrahim Ibnusaud. [Extracted from the article]

In this study, we evaluated the cancer cell killing activity of koji mold-derived extracts using several solvents. The koji mold lipid extract (KML) exhibited potent cytotoxicity against a human leukemia cell line. Fractionation of the KML via silica gel chromatography revealed the presence of active components in fraction (Fr.) 6. Cytotoxic effects of Fr. 6 were inhibited by the ferroptosis inhibitors, ferrostatin-1 and SRS11-92, and the iron chelator, deferoxamine. Interestingly, ferroptosis inhibitors failed to prevent the KML-induced cell death. Fr. 6 decreased the expression of glutathione peroxidase 4 (GPx4) and increased the level of peroxidized plasma membrane lipids. Furthermore, Fr. 6 decreased the intracellular glutathione levels. Overall, our results suggest that Fr. 6 included in KML induces ferroptosis in HL-60 cells. [ABSTRACT FROM AUTHOR]

Strawberry guava is the fruit of Psidium littorale, which grows in tropical regions. Few studies have examined the hydrophobic compounds and biological activities of this fruit. Therefore, we purified lipophilic compounds of strawberry guava and examined their effects on epidermal and blood vessel barrier functions as well as their anti-melanogenic activity. Lipophilic compounds were isolated by silica gel column chromatography followed by reversed-phase HPLC with MeOH from an EtOH extract of the fruit. Isolated compounds were identified by comparing NMR and MS spectra with those of reference values. The effects of these compounds on epidermal barrier function were evaluated by measuring transepidermal water loss (TEWL) using reconstructed human epidermal keratinocytes (RHEKs). Blood vessel barrier function was examined using dye permeability through human umbilical vein endothelial cell (HUVEC) layers. Anti-melanogenic activity was assessed by theophylline-induced melanogenesis in B16 melanoma cells. We isolated six glucosylceramides (GlcCers) and three digalactosyldiacylglycerols (DGDGs). Only GlcCer[t18:1(8Z)/23:0] significantly lowered TEWL in RHEKs, while GlcCer[t18:1(8Z)/24:0] induced a slight reduction. Regarding the permeability of the HUVEC layer, GlcCer[d18:2(4E,8Z)/16:0] and DGDG (1,2-dilinolenoyl-3-digalactosylglycerol) significantly suppressed dye permeability and this effect was accompanied by the expression of VE-cadherin, which facilitates cell-to-cell adhesion. GlcCers and DGDGs did not exhibit anti-melanogenic activity. Therefore, strawberry guava containing specific GlcCers and DGDGs may promote epidermal and blood vessel barrier functions. [ABSTRACT FROM AUTHOR]

Several cottonseed varieties are cultivated in different countries. Each variety produces a different amount of gossypol as a natural toxic compound. The rising interest in cottonseed products (oil and feed) increases the demand for establishing simple methods for gossypol detection. Silica gel-based methods are ideal for its isolation, purification, and characterization. Silica gel-based methods are variants and can be used as simple methods for tracking plants' compounds. In this study, gossypol was isolated, characterized, and purified as gossypol acetic acid in the form of yellow crystals. Methods used for its characterization were TLC, preparative TLC, silica gel column, UV/IR spectrophotometer, and HPLC (robust spherical silica gel). A comparative study between its amount in both the Egyptian and Chinese varieties was performed. Under the experimental conditions, the Egyptian's cottonseed contains 8.705 gm/kg, while the Chinese's cottonseed contains 5.395 gm/kg. The TLC used in this study proved to be fast, accurate, and inexpensive. It can be used for gossypol acetic acid evaluation and quantification. Additionally, using TLC as a pre-purification step will give a pre-judgment for the sample's purity and quality. This step will protect the expensive HPLC silica gel-based column from any unexpected impurities. During each step, the silica gel itself could be simply removed by paper filtration. Collectively, the different silica gel-based methods as well as the other used methods are recommended for better Gossypol acetic acid isolation, purification, and characterization, as well as for maintaining HPLC columns. [ABSTRACT FROM AUTHOR]

Geochemical and biomarker characteristics of representative crude oil samples from selected fields in southern Nigeria were evaluated to determine the organic matter input, origin of biological material, depositional environment, thermal maturity, and genetic relationship between the oils. Four crude oil samples were obtained from various oil producing fields from Delta, Bayelsa and Abia state in southern Nigeria and labeled Kwale (KW), Kolo creek (KLC), Owaza (OWA1 and OWA2). The crude oil samples were fractionated into saturates, aromatic hydrocarbons and polar compounds using column chromatography on silica gel thereafter, analyzed using Gas chromatography-mass spectrometry (GC–MS). The calculated ratios of normal alkanes, acyclic isoprenoids, carbon preference index (CPI), hopanes, and steranes showed the following results: Pr/Ph (0.34 to 0.89); C29/C27 (0.78 to 1.25); 20S/(20S + 20R)C29sterane (0.28 to 0.66); 22S/(22S + 22R)C32 homohopane (0.17 to 0.23); CPI (0.96 to 0.98); Ts/Ts + Tm (0.46 to 0.50); and sterane/hopane (0.16 to 0.87). The results obtained were used to correlate the crude oils with respect to depositional environment, thermal maturity, and organic matter source. The Pr/Ph ratios of KW and KLC were less than one, and the cross-plot of Pr/nC17 versus Ph/nC18 of KW and KLC suggested that the oils were deposited under anoxic environments, whereas OWA1 and OWA2 indicated oxic conditions with no biodegradation. From the calculated ratios of 22S (22S + 22R)C32 homohopane and CPI, the oils were mature and had entered the generating window. Sample OWA1 is the most mature, while KLC is the least mature. The calculated ratios also showed that the four oil samples were from a shale source rock with both terrestrial and marine inputs. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of pentasubstituted 4H-pyran derivatives using N-heterocyclic carbene (NHC) catalysis. The researchers developed a new annulation reaction that allows for the rapid synthesis of these derivatives from readily available starting materials. They tested different substrates and found that both electron-withdrawing and electron-donating groups were tolerated. The researchers also explored the effect of different substituents and successfully conducted the reaction on a larger scale. They proposed a plausible reaction mechanism and concluded that their method could be useful for synthesizing functional molecules containing the 4H-pyran group. [Extracted from the article]

This document provides a comprehensive overview of the synthesis and characterization of various organic compounds. The compounds were synthesized using a general procedure and their structures were confirmed using analytical techniques such as IR spectroscopy, NMR spectroscopy, and high-resolution mass spectrometry. The document also acknowledges the funding support and provides additional supporting information. This resource is valuable for researchers studying the synthesis and characterization of these specific compounds. [Extracted from the article]

This article discusses the synthesis and characterization of thiosulfonates, sulfonyl hydrazides, and sulfonothioate compounds. The authors explore different methods for synthesizing these compounds and provide details on reaction conditions, yields, and physical properties. The text highlights the potential applications of these compounds in medicinal chemistry, drug design, and organic synthesis. The information provided can be valuable for researchers studying these compounds and their properties. The supporting information for the article is available online. [Extracted from the article]

It is of great importance to reduce the production cost of biosurfactants, which have application areas in a wide range of industrial processes with their antimicrobial and anti-biofilm properties. Accordingly, it was aimed to determine the potent low-cost waste for the cost-effective biosurfactant production by environmental origin Bacillus sp. strains. 2% (v/v) of individual bacterial strain was inoculated into 50 mL of Bushnell Haas medium (pH:7.0) containing 8% (v/v) of each low-cost waste, 1% (w/v) yeast extract and 0.1% (v/v) trace element, and incubation period was carried out at 30 °C and 150 rpm for 7 days. Following the extraction of the culture supernatants, maximum biosurfactant yielded 0.139 ± 0.003 with potato wastewater by potent Bacillus subtilis MG847158.1. Hemolytic activity, 7.70 ± 0.35 mm zone diameter for oil displacement, 50.1 ± 0.8 emulsification index, 89.73 ± 0.9% bacterial adhesion, and decreasing of surface tension from 72.80 ± 0.1 mN/m to 23.97 ± 0.05 mN/m were also obtained. The extracted biosurfactant was further purified by silica gel column chromatography and characterized as lipopeptide by TLC, FT-IR, NMR, and SEM. In addition to being quite effective against both Gram-negative and Gram-positive bacteria, the highest antimicrobial and anti-biofilm activities of biosurfactant were against two Gram-negatives: E. coli (18.1 ± 0.8 mm) (MIC 1 mg mL−1, MBC 2 mg mL-1) and K. pneumoniae (97%) strains. To sum up, it is the first study to emphasize that the produced biosurfactant with low-cost potato wastewater can be used as an alternative to commercial antimicrobial agents. [ABSTRACT FROM AUTHOR]

This article discusses a study on the development of a metal-free approach for selectively adding oxygen to specific carbon-hydrogen bonds in certain compounds using visible-light photoredox catalysis. The researchers used acridinium dyes and a hydrogen atom transfer reagent to achieve this transformation. They optimized the reaction conditions using cyclohexene as a model compound and found that specific conditions, including the use of a particular base and reagent, blue LED light, and air, resulted in the desired product in moderate yield. Control experiments confirmed the importance of light and air in the reaction, and the concentration of oxygen in the reaction media affected the outcome. The researchers also successfully applied this method to other cyclic compounds and more complex molecules. [Extracted from the article]

This article discusses the design and synthesis of heterocyclic core scaffolds for drug discovery research. The researchers were able to generate unique heterocyclic skeletons from a common derivative and discovered that an amino moiety could be added to the ring system through annulative reactions with quinones. The target compound possesses both carbonyl and amino groups, similar to biologically active quinones. The researchers optimized the reaction conditions and found that the use of Cu(OAc)2 as a catalyst provided the desired product in high yield. The synthesis of various compounds was also explored. These compounds were tested for their anticancer effects and showed good inhibitory activities against human hepatocellular cells and prostate adenocarcinoma cells. The study suggests that these compounds could be further developed as potential anticancer agents for the treatment of liver and prostate cancer. The given text provides data and information related to the synthesis and characterization of compounds 4a, 4b, 4c, 4d, and 4e. The compounds were synthesized using a general procedure involving the reaction of naphthoquinone with different reagents. The compounds were obtained in good yields and characterized using various techniques such as NMR and HRMS. The data presented in the text can be used by researchers studying the cytotoxic effects of these compounds on HepG2 and PC-3 cells. The document provides information on the synthesis and characterization of various compounds. The compounds are described in terms of their chemical structures [Extracted from the article]

This article explores the electrochemical hydro- and deuterocarboxylation of allenes using carbon dioxide (CO2) and deuterium oxide (D2O) as starting materials. The authors discuss the challenges of activating CO2 and propose photochemical and electrochemical methods as potential solutions. They present their own findings on the electrochemical hydrocarboxylation and deuterocarboxylation of allenes, demonstrating good regioselectivity and high yields of carboxylic acids. The authors suggest possible mechanisms for these reactions and highlight their potential applications in reaction mechanism studies and drug development. The article also provides detailed experimental procedures and results, including information on the synthesis and characterization of various compounds. [Extracted from the article]

This article discusses the development of a visible-light-mediated three-component radical difunctionalization of alkenes, which allows for the synthesis of alkynyl-functionalized organoborons. The researchers optimized the reaction conditions and found that the use of specific reagents and a photocatalyst led to the desired product in good yield. The reaction was found to be chemoselective and had a broad substrate scope. The authors propose a plausible reaction mechanism based on their experimental findings. This method has potential applications in drug discovery and offers a feasible strategy for constructing alkynyl-functionalized organoborons. The text also provides detailed information about the physical and chemical properties of the product. Additionally, the document provides information on the synthesis and characterization of various chemical compounds, including derivatives of chroman and imidazole. The compounds are described in terms of their physical properties and spectroscopic data. Supporting information is available online. [Extracted from the article]

This article discusses the metal-free synthesis of trifluoromethyl carbinol-containing imidazo[1,2-a]pyridines through dehydrative coupling. Trifluoromethyl-containing compounds are important in various fields due to their biological activity and stability. Imidazo[1,2-a]pyridines are commonly found in pharmaceuticals, and the construction of CF3-containing imidazo[1,2-a]pyridines is valuable for drug discovery. The use of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as a medium for organic synthesis has been explored, and it has been found to promote the hydroxy-trifluoromethylation of imidazo[1,2-a]pyridines with trifluoroacetaldehyde. The optimized reaction conditions using HFIP as a solvent resulted in good yields of the desired products. The substrate scope of this process was also investigated, demonstrating its generality and practicality. This article describes a novel approach for the synthesis of trifluoromethyl carbinol-containing imidazo[1,2-a]pyridines using imidazo[1,2-a]pyridines and trifluoroacetaldehyde via a dehydrative cross-coupling process. The reaction was promoted by HFIP and exhibited wide substrate generality, excellent functional group tolerance, and mild reaction conditions. [Extracted from the article]

This document provides technical information about the synthesis and characterization of alkyl ether phospholipids, specifically 1-alkyl-2-acyl-sn-glycero-3-phosphoethanolamines (1-alkyl-2-acyl-GPEs). The authors have developed a novel phosphorylating agent that allows for the synthesis of these compounds, overcoming limitations of traditional methods. The document includes detailed synthesis routes, purification methods, and analytical test results for different derivatives of the compound. The compounds are referred to as 1-alkyl-2-acyl-GPE 12a, 12b, and 12c, and the document also includes an acknowledgment and dedication to Professor Koichi Narasaka. [Extracted from the article]

This study aimed to isolate and purify resveratrol and oxyresveratrol from the heartwoods of Maclura cochinchinensis, and to evaluate their inhibitory effects on melanogenesis in B16F10 murine melanoma cells. A methanol maceration process yielded a crude extract comprising 24.86% of the initial mass, which was subsequently analyzed through HPTLC, HPLC, and LC-MS/MS. These analyses revealed the presence of resveratrol and oxyresveratrol at concentrations of 4.32 mg/g and 33.6 mg/g in the extract, respectively. Initial purification employing food-grade silica gel column chromatography separated the extract into two fractions: FA, exhibiting potent inhibition of both tyrosinase activity and melanogenesis, and FM, showing no such inhibitory activity. Further purification processes led to the isolation of fractions Y11 and Gn12 with enhanced concentrations of resveratrol (94.9 and 110.21 mg/g, respectively) and fractions Gn15 and Gn16 with elevated levels of oxyresveratrol (321.93 and 274.59 mg/g, respectively), all of which significantly reduced melanin synthesis. These outcomes affirm the substantial presence of resveratrol and oxyresveratrol in the heartwood of M. cochinchinensis, indicating their promising role as natural agents for skin lightening. [ABSTRACT FROM AUTHOR]

Nowadays, infectious diseases pose an alarming global threat to human health. The genus Senna is among the most well-known taxonomic categories commonly used in folk medicine to confront these challenges. Motivated by its traditional uses, a comprehensive study was conducted on the roots extract of Senna siamea, aiming to address the in vitro antibacterial and antioxidant efficacy of phytochemicals from the dichloromethane: methanol (1:1) roots extract of the plant, along with in silico computational studies. The separation of compounds was achieved using silica gel column chromatography. Whereas, the antibacterial and antioxidant activities were examined using paper disc diffusion and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, respectively. Silica gel column chromatography of the dichloromethane: methanol (1:1) roots extract afforded lupeol (1), β-sitosterol (2a) and stigmasterol (2b), chrysophanol (3), betulinic acid (4), and glyceryl-1-hexacosanoate (5). Although these compounds have been previously reported from the plant, proof of their medicinal applications via in vitro and in silico studies is still lacking. Notably, our findings showed remarkable inhibition zones by the extract (18.00 ± 0.00 mm and 17.17 ± 0.24 mm) against E. coli and S. aureus, respectively, at 50 mg/mL compared to ciprofloxacin (23.33 ± 0.47 mm and 22.00 ± 0.00 mm, respectively), showcasing its potential antibacterial efficiency. Considerable inhibition zones were also recorded by chrysophanol (3) against E. coli (16.33 ± 0.24 mm) and S. pyogenes (16.00 ± 0.00 mm) at 2 mg/mL, compared to ciprofloxacin which showed 23.33 ± 0.47 mm and 21.67 ± 0.47 mm, respectively, signifying its potent antibacterial activities. In addition, the crude extract and chrysophanol (3) exhibited substantial IC50 values (1.24 and 1.71 µg/mL, respectively), suggesting their significant antioxidant potential compared to that of ascorbic acid (IC50: 0.53 µg/mL). Chrysophanol (3) fulfilled Lipinski's rule with no violation and lupeol (1), β-sitosterol (2a), stigmasterol (2b), betulinic acid (4), and glyceryl-1-hexacosanoate (5) displayed one violation each which were in favor of the drug-likeness predictions. All the compounds exhibited no cytotoxicity and except betulinic acid (4), all the compounds also showed no carcinogenicity properties which were consistent with the prediction results of ciprofloxacin. The molecular docking computations revealed that all the compound isolates displayed strong and nearly strong binding affinities against all protein targets, ranging from − 6.6 kcal/mol to -9.2 kcal/mol (lupeol (1) against E. coli DNA gyrase B and topoisomerase II α, respectively). Thus, the present findings suggest the roots of Senna siamea for potential medicinal applications against multi-drug resistant pathogens hence validating its ethno-medicinal uses. [ABSTRACT FROM AUTHOR]

This work is focused on the characterization of the composition of a CO2 supercritical fluid extract of Aquilaria sinensis (Chinese agarwood) collected in the Dongguan area (China) and infected by mechanical methods. The constituents of this extract were analyzed by gas chromatography–mass spectrometry (GC-MS) and quantified accurately by gas chromatography with a flame ionization detector (GC-FID), using an internal reference and predicted response factors. Since a significant number of components of this extract remained non-identified after the initial GC-MS analysis of the whole extract, its fractionation by chromatography on silica gel helped to characterize several additional constituents by isolation and structural analysis by NMR spectroscopy. The main components are the classical agarwood chromones (Flindersia chromone and its mono-, di-, and trimethoxylated analogues (respectively, 11.01% and 0.11–4.02%) along with sesquiterpenic constituents typically found in agarwood essential oils, like baimuxinal (1.90%) and kusunol (1.24%), as well as less common selinane dialdehydes (1.58–2.27%) recently described in the literature. Moreover, the structure and stereochemistry of a new sesquiterpenic alcohol, 14β,15β-dimethyl-7αH-eremophila-9,11-dien-8β-ol (0.67%), was determined unambiguously by the combination of structural analysis (NMR, MS), hemisynthesis, and total synthesis, leading to dihydrokaranone and a neopetasane epimer. [ABSTRACT FROM AUTHOR]

This article explores the development of a method for the asymmetric β-borylation of α,β-unsaturated acyl silanes using copper catalysis. The authors conducted experiments to optimize the reaction conditions and found that a ligand-free reaction produced the best results. They also investigated the range of the reaction and successfully synthesized various β-boryl acyl silanes with different substituents. The authors suggest that the inclusion of Li(acac) helps prevent undesired cleavage of the acyl silane moiety. Overall, this research provides valuable insights into the optimization and scope of a Cu I -catalyzed conjugate borylation reaction, which may have potential applications in further studies of bifunctional molecules. [Extracted from the article]

This article explores the regioselectivity during the formation of aminoboronates from epoxides. The researchers aimed to investigate the stability of unprotected α-boryl aziridines and the effect of B-N interaction on their stability. They successfully isolated aziridine MIDA boronate through the Staudinger reaction and discovered a rare case of a geminal azidoalcohol. The researchers also attempted to synthesize the desired azidoalcohol through different approaches but were unsuccessful. The synthesis of unprotected aziridine MIDA boronate provides a useful building block for further transformations. [Extracted from the article]

This document provides information on the synthesis and characterization of various isoxazole compounds. The compounds were synthesized using specific reactions and their yields, physical properties, and spectroscopic data are reported. The information presented can be useful for researchers studying isoxazole compounds and their properties. The authors acknowledge the support of DST and SCXRD LAB, SAIF, IIT Madras for single-crystal X-ray analysis. Supporting information for the article is available online. [Extracted from the article]

This document provides detailed information on the synthesis and characterization of various compounds through a series of chemical reactions. The compounds include amino acid derivatives and other organic compounds. The document includes information on the starting materials, reagents, reaction conditions, yields, physical properties, and spectroscopic data of the compounds. The research was supported by the MEXT Project and Tokuyama Corporation. Additional supporting information can be found online. [Extracted from the article]

Background: The development of resistance by Plasmodium falciparum is a burdening hazard that continues to undermine the strides made to alleviate malaria. As such, there is an increasing need to find new alternative strategies. This study evaluated and validated 2 medicinal plants used in traditional medicine to treat malaria. Methods: Inspired by their ethnobotanical reputation of being effective against malaria, Ziziphus mucronata and Xysmalobium undulutum were collected and sequentially extracted using hexane (HEX), ethyl acetate (ETA), Dichloromethane (DCM) and methanol (MTL). The resulting crude extracts were screened for their anti-malarial and cytotoxic potential using the parasite lactate dehydrogenase (pLDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, respectively. This was followed by isolating the active compounds from the DCM extract of Z. mucronata using silica gel chromatography and structural elucidation using spectroscopic techniques (NMR: 1H, 12C, and DEPT). The active compounds were then targeted against P. falciparum heat shock protein 70–1 (PfHsp70-1) using Autodock Vina, followed by in vitro validation assays using ultraviolet–visible (UV–VIS) spectroscopy and the malate dehydrogenase (MDH) chaperone activity assay. Results: The extracts except those of methanol displayed anti-malarial potential with varying IC50 values, Z. mucronata HEX (11.69 ± 3.84 µg/mL), ETA (7.25 ± 1.41 µg/mL), DCM (5.49 ± 0.03 µg/mL), and X. undulutum HEX (4.9 ± 0.037 µg/mL), ETA (17.46 ± 0.024 µg/mL) and DCM (19.27 ± 0.492 µg/mL). The extracts exhibited minimal cytotoxicity except for the ETA and DCM of Z. mucronata with CC50 values of 10.96 and 10.01 µg/mL, respectively. Isolation and structural characterization of the active compounds from the DCM extracts revealed that betulinic acid (19.95 ± 1.53 µg/mL) and lupeol (7.56 ± 2.03 µg/mL) were responsible for the anti-malarial activity and had no considerable cytotoxicity (CC50 > µg/mL). Molecular docking suggested strong binding between PfHsp70-1, betulinic acid (− 6.8 kcal/mol), and lupeol (− 6.9 kcal/mol). Meanwhile, the in vitro validation assays revealed the disruption of the protein structural elements and chaperone function. Conclusion: This study proves that X undulutum and Z. mucronata have anti-malarial potential and that betulinic acid and lupeol are responsible for the activity seen on Z. mucronata. They also make a case for guided purification of new phytochemicals in the other extracts and support the notion of considering medicinal plants to discover new anti-malarials. [ABSTRACT FROM AUTHOR]

Normal-phase liquid chromatography (NPLC) plays a pivotal role in the rapid separation of non-polar compounds, facilitating isomer separation and finding applications in various crucial areas where aprotic solvents are necessary. Similar to reversed-phase liquid chromatography (RPLC), NPLC requires a robust and sensitive detector to unequivocally identify the analytes, such as a mass spectrometer. However, coupling NPLC with mass spectrometry (MS) poses challenges due to the incompatibility between the non-polar solvents used as the mobile phase and the primary ionization techniques employed in MS. Several analytical methods have been developed to combine NPLC with electrospray ionization (ESI), but these methods are restricted to the analysis of polar compounds. In most cases, atmospheric pressure chemical ionization (APCI) becomes necessary to expand the range of analysis applications. To overcome these limitations and fully realize the potential of NPLC-MS coupling, a technique termed liquid electron ionization-mass spectrometry (LEI-MS) can be used. LEI-MS offers a straightforward solution by enabling the effective coupling of NPLC with both low and high-resolution MS. LEI allows for the comprehensive analysis of non-polar compounds and provides a powerful tool for isomer separation and precise identification of analytes. Optimal separations, mass spectral qualities, and matches with the NIST library were obtained in both configurations, demonstrating the potential of the proposed approach. [ABSTRACT FROM AUTHOR]

Sugar esters in tobacco play an important role as precursors generating tobacco aroma species, and their presence significantly influence the quality of tobacco leaves. Typically present in trace amounts, sugar esters in tobacco exhibit a diverse range of isomers, making their separation and analysis a significant challenge. To address this challenge, mass spectrometry has been extensively applied for the identification and differentiation of various of sugar ester compounds in tobacco. However, there is no study regarding the separation and analysis of sugar esters specifically within Burley tobacco leaves. In this research, Burley tobacco leaf extracts were obtained using the solvent extraction technique, and underwent separation using silica gel column chromatography. Ultimately, the fractions comprising glucose esters and various sucrose esters were collected, respectively. The structural identification of these acquired sugar esters was achieved by liquid chromatography-tandem mass spectrometry (LC-MSn). According to the MS² fragment ions of sucrose esters, the mass difference of 162.05 and 204.06 was mainly observed, implying an unbound fructose ring and a fructose ring acetylated in the sucrose ester, respectively. The composition information of fatty acids substituted to the glucose ring were further revealed based on the MS³ or MS² fragment ions from sucrose esters or glucose esters. By combining the relative molecular weight, molecular formula, and the above mentioned fragment information, four types of sucrose esters from SE-I to SE-IV (referred to as compound 1-20) and two types of glucose esters GE-I to GE-II (referred to as compound 21-31) were finally identified. Among them, four sucrose esters of distinct molecular weights were newly discovered, and the structures of eight glucose esters were reported for the first time in cultivated tobacco. The sugar esters were analyzed by high-resolution mass spectrometry, which could effectively distinguish the number of fatty acids substituted on glucose and fructose, thus facilitating the differentiation of sugar ester types. Nevertheless, the identification of sugar esters in this study was limited to determine the characteristic skeleton and fatty acid composition. Detailed information on specific fatty acid types and substitution sites require further investigation using NMR technique. In conclusion, these results contribute to the current knowledge of sugar esters in Burley tobacco by expanding the range of identified types and providing high-resolution mass spectrometry data for various types of sugar esters for the first time. These findings hold significant reference value for the analysis, identification, and metabolism of different sucrose and glucose esters in tobacco. [ABSTRACT FROM AUTHOR]

This article, published in Chemistry of Natural Compounds, explores the chemical constituents of Swertia chirayita, a plant used in traditional medicine. The study focused on the ethyl acetate extract of S. chirayita and identified 15 compounds, some of which were reported for the first time from the family Gentianaceae. The chemical structures of these compounds were confirmed through NMR and MS analyses. The document provides a list of the compounds, including nobiletin, 4-Epihederagenin, 2-Epicorosolic acid, ursolic acid, 23-Hydroxyursolic acid, β-Daucosterol, Swerimilegenin I, Pyrocatechol, Syringic acid, Erythrocentaurin, and Amarogentin, along with their properties such as chemical formula, molecular weight, and spectroscopic data. The research was supported by the Natural Science Foundation of Nanjing University of Chinese Medicine. [Extracted from the article]

This article discusses the cytotoxic constituents found in the fruits of Garcinia schomburgkiana, a tree commonly known as Ma-dan in Thai. The study isolated fourteen compounds from the fruits, including volkensiflavone, morelloflavone, and oblongifolin C, which have potential cytotoxic properties against various cancer cell lines. The article provides chemical data for several compounds, including their molecular formulas, NMR spectra, and mass spectrometry data. The research was supported by Thammasat University Research Unit in Natural Products Chemistry and Bioactivities and Thailand Science Research and Innovation Fundamental Fund. [Extracted from the article]

This article discusses the synthesis of amides and peptides using a new acid activator called [4-(acetylamino)phenyl]imidodisulfuryl difluoride (AISF). The authors optimized the reaction conditions and found that the method was suitable for various carboxylic acids, amines, and amino acids. The protocol was demonstrated to be racemization-free and suitable for gram-scale reactions. The article also provides detailed information about the chemical properties and characterization of various compounds, including their yields, physical properties, and spectroscopic data. The supporting information for the article is available online. [Extracted from the article]

This document provides technical information about the synthesis and characterization of three chemical compounds. The compounds are described in terms of their nuclear magnetic resonance (NMR) spectra, high-resolution mass spectrometry (HRMS) data, and physical properties. The text also acknowledges financial support from the CAS-TWAS fellowship. The information is presented in a scientific manner and may be useful for researchers studying organic chemistry. [Extracted from the article]

This article provides a detailed description of the synthesis and characterization of several compounds, specifically cis-1,3-dialkylindanes. The authors focus on the synthesis of epi-mutisianthol and epi-jungianol, two representative 1,3-dialkylindane sesquiterpenes. They successfully complete the synthesis of these compounds in six steps with high yields, demonstrating the potential for further exploration of their structure-activity relationships. The document includes data such as melting points, infrared spectra, and nuclear magnetic resonance spectra for each compound, and the supporting information is available online. [Extracted from the article]

This document provides information on various compounds, specifically N-formyl derivatives, and their spectroscopic data. The compounds mentioned include a wide range of derivatives with different functional groups. The compounds were purified and their spectroscopic data were compared to existing literature, confirming their identities. The document also acknowledges the scholarship awarded to one of the researchers. [Extracted from the article]

This article discusses the development of a copper-catalyzed asymmetric esterification reaction for propargylic C-H bonds, which allows for the construction of chiral propargylic esters. The researchers achieved good yields and high enantioselectivities using tridentate oxazoline copper complexes as catalysts. The reaction was not significantly affected by various substituents on the aromatic ring, and the enantioselectivity was retained in subsequent transformations. The document provides detailed information on the synthesis and characterization of various ester compounds, including reaction conditions, yields, enantiomeric ratios, and physical properties. It also includes spectroscopic data such as NMR spectra, HRMS data, HPLC analysis, and melting points. The compounds synthesized have potential applications in pharmaceutical and natural product synthesis. [Extracted from the article]

This document summarizes a study on the synthesis and characterization of various compounds, including trifluoromethyl arenes. The study focuses on the hydrolysis of the trifluoromethyl group to carboxylic acid, which is challenging but important for pharmaceutical applications. The authors propose a method using a combined base system that efficiently mediates this transformation. The document provides experimental procedures, spectral data, and acknowledges the use of an EPR apparatus from Tohoku University. The data obtained for the compounds synthesized in the study match those reported in the literature. [Extracted from the article]

This article discusses the organocatalytic approach to the enantioselective total synthesis of (+)-Serinolamides A and B and (+)-Lacosamide. It explores the role of the endocannabinoid system in various pathophysiologies and the synthesis and isolation of endogenous ligands. The authors present a new and efficient method for synthesizing these compounds using asymmetric organocatalysis, which allows for stereochemical variations and easy access to related compounds. The document provides detailed information on the purification, characterization, and yields of the synthesized compounds, as well as the determination of enantiomeric excess. The supporting information for this article can be found online. [Extracted from the article]