Search

Encequidar mesylate salt is a novel, little‐absorbed P‐glycoprotein (P‐gp) that facilitates oral absorption. It is a substance that stops the P‐gp adenosine triphosphate‐binding cassette transporter from working. To ascertain the drug substance's inherent stability, it underwent stress testing under a variety of degradation conditions, including acidic hydrolysis, alkaline hydrolysis, oxidative, thermal, and photolytic, in accordance with regulatory requirements. It was discovered that the drug substance is highly unstable in alkaline conditions, and the degradation leads to the formation of two unique, unknown degradation products. Utilizing UHPLC–ESI/MS for identification and mass‐triggered preparative HPLC for isolation, the degradants' structures were definitively determined by using high‐resolution mass spectrometry and 2D NMR methodologies. These unique degradation products were determined to be novel impurities of the encequidar drug substance and were firmly proven to be its hydrolysis components on the basis of spectral and chromatographic data. Possible potential mechanisms have been proposed to explain the formation of the degradants. [ABSTRACT FROM AUTHOR]

The Jurassic relict Royal fern, Osmunda regalis L., is widely distributed across temperate zones in the Northern and Southern hemispheres. Even though this species has been utilised for centuries as a medicinal plant, its phytochemical composition mainly remains unknown. As part of our ongoing research to identify potential lead compounds for future anticancer drugs, 17 natural products were characterised from the aerial parts of Osmunda regalis L. Fifteen of these compounds were identified in this species for the first time, including the six previously undescribed compounds kaempferol 3-O-(2"-O-(2"'-α-rhamnopyranosyl)-β-glucopyranosyl)-β-glucopyranoside, quercetin 3-O-(2"-O-(2"'-α-rhamnopyranosyl)-β-glucopyranosyl)-β-glucopyranoside, kaempferol 3-O-(2"-O-(2"'-α-rhamnopyranosyl-6"'-O-(E)-caffeoyl-)-β-glucopyranosyl)-β-glucopyranoside, 3-methoxy-5-hydroxy-4-olide, 4-hydroxy-3-(3'-hydroxy-4'-(hydroxyethyl)-oxotetrafuranone-5-methyl tetrahydropyranone, and 4-O-(5-hydroxy-4-oxohexanoyl) osmundalactone. The molecular structures were determined by combining several 1D and 2D NMR experiments, circular dichroism spectroscopy, and HRMS. Determination of cytotoxicity against AML MOLM-13, H9c2, and NRK cell lines showed that two isolated lactones exhibited significant cytotoxic activity. [ABSTRACT FROM AUTHOR]

The content of unfrozen water in the freezing process of coal body affects the microscopic pore structure and macroscopic mechanical properties of coal body and determines the permeability-enhancement effect of coal seam and the extraction efficiency of coal mine gas. To investigate the evolution mechanism of unfrozen water content in the melting process of lignite, this paper takes the melting process of lignite liquid nitrogen after freezing for 150 min as the research object and quantifies the spatial change process of unfrozen water distribution based on two-dimensional nuclear magnetic resonance technology. Through the accurate interpretation of the superimposed signals of different fluids, the 2D NMR technique can more easily obtain the spatial distribution of different fluids and even the specific content of fluids in different pores in coals. The results show that at −196 °C, the unfrozen water mainly existed in the small coal pore and the small ice pore in the large pore. As the temperature rose, the pores melted, and free water began to be produced. The mathematical model analysis shows that there was intermolecular potential energy between fluid molecules and the coal pore wall, and the pore wall exerted a part of pressure on its internal fluid, and the pressure affected the melting point of pore ice with pore diameter and melting temperature, resulting in the difference of unfrozen water content. [ABSTRACT FROM AUTHOR]

Three undescribed oleanolic acid glycosides, together with four known ones, were isolated from root barks of two species of Olax : 3- O -α-L-rhamnopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyloleanolic acid and 3- O -α-L-rhamnopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyloleanolic acid 28- O -β-D-glucopyranosyl ester from Olax wildemanii , and 3- O -β-D-glucopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→3)]-β-D-glucuronopyranosyloleanolic acid from Olax subscorpioidea. Their structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments in combination with mass spectrometry. These molecules showed no antimicrobial activity against Candida albicans, Staphylococcus aureus and Pseudomonas aeruginosa. [Display omitted] • Seven different oleanolic acid glycosides were isolated. • Their structures were elucidated by extensive spectroscopic analyses. • The chemotaxonomy of the Olax genus was discussed, based on the structure of the isolated glycosides. • The antimicrobial activity of some isolated compounds was evaluated. • The lack of activity reinforces the previous structure/relationships conclusions. [ABSTRACT FROM AUTHOR]

Position of glycosidic linkages in oligosaccharide was confirmed by alditol acetate. methylation/acid hydrolysis in traditional studies. Later. core units and structure reporter group theory along with comparison of chemical shifts of natural and acetylated oligosaccharides were used for confirming the position of glycosidic linkages. These methods were. however. inappropriate and imperfect in certain cases. In recent times. 2D heteronuclear multiple bond correlation (HMBC) NMR experiments are being used for this purpose. making it possible to fix the position of glycosidic linkages unequivocally. In this experiment the multiple bond correlation of anomeric carbon of next monosaccharide gives a cross peak with the methine proton of the previous monosaccharide in an oligosaccharide chain. It becomes more complicated when the oligosaccharide is comprised of long or branched chains. but due to some proximal and steric hindrances this correlation is often not observed restricting the process of sequencing in milk oligosaccharides. In these circumstances. an alternative experiment. Reverse HMBC is used and is explained for the first time. meaning thereby. we observe the cross peak between methine carbon of the monosaccharide under observation with the anomeric proton of the next monosaccharide. In the present paper. Reverse HMBC technique for structure elucidation of novel heptaglycoside named Arkaroside from Tharparkar cow milk has been used. [ABSTRACT FROM AUTHOR]

Milk is a biofluid. essential for growth and development of infants and is comprised of protein. fat and carbohydrates in the form of lactose and oligosaccharides. These oligosaccharides are responsible for any specific biological activity of the particular milk. Camel milk is called gold of dessert and has antitubercular. antiviral and antitumor properties. Camel milk also contains disease-fighting properties and have hypogylcemic activity. Keeping in mind, the usefulness of camel's milk and role of oligosaccharides present in it for treatment of various diseases. It was collected in bulk and processed by modified method of Kobata and Ginsberg method followed by Gel filtration. HPLC and silica column chromatography which led to isolation of a novel nonasaccharide. Ramedrose and its structure was elucidated with the help of ¹H, 13C NMR and 2D NMR i.e. HMBC. HSQC. COSY and TOCSY and Mass spectrometry which is as under (1→3)-α-D-Glc(1→3)-β-D-Glc(1→3)-β-D-Glc(1→3)-β-D-Gal(1→3)-β-D-GlcNAc(1→3)-β-D-GalNAc(1→4)-β-D-Glc ... [ABSTRACT FROM AUTHOR]

The present study was conducted to compare leaf extracts of Y. gloriosa, Y. treculeana, Y. filamentosa and Y. aloifolia. Plant extracts were obtained by sequential extraction with 50% and 100% methanol using the pressurized liquid extraction method. General comparative analysis of Yucca extracts was performed by 2 D-NMR. The presence of various biologically active components in the extracts was shown, among which steroid saponins predominate. The use of LC-MS and LC-HRMS methods with electrospray ionization made it possible to conduct a comparative analysis of Yucca steroidal saponins. The 33 steroidal saponins of various structures were found. The presence of three characteristic saponins in all Yucca species was shown: yuccaloeside C, yuccaloeside E and yuccaloeside B. The results obtained can be used to control the quality of plant materials and products. [ABSTRACT FROM AUTHOR]

The reaction of butyryl chloride with ethynylbenzene in the presence of AlCl3 afforded a mixture of the Z/E‐isomers of 1‐chloro‐2‐phenylhex‐1‐en‐3‐one. 1,2‐Diphenylethyne under these conditions gave a novel polycarbocycle core, 6aH‐benzo[a]fluorene. The chemical structure of 11‐chloro‐5,6‐diphenyl‐6a‐propyl‐6aH‐benzo[a]fluorene was established by means of IE‐MS, 1H, 13C NMR, COSY, HSQC, HMBC, and 2D INADEQUATE technique. [ABSTRACT FROM AUTHOR]

Bile acids are the main body of enterohepatic circulation in vivo. They have essential functions such as emulsifying fat, bacteriostasis and regulating multiple metabolic pathways as signal molecules. However, the assignments of NMR signals for some low-concentration bile acids are still needed. This study combined 1D nuclear magnetic resonance (NMR) and 2D NMR techniques including 1H–1H correlation spectroscopy (COSY), 1H–1H total correlation spectroscopy (TOCSY), 1H J-resolved spectroscopy (J-Res), 1H–13C heteronuclear single quantum coherence spectroscopy (HSQC), and 1H–13C heteronuclear multiple bond correlation spectroscopy (HMBC) to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH (∼7.4) and nine bile acids in methanol. These data are of importance to the NMR-based studies on lipid digestion, absorption, and metabolism.

Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for identifying the various allomorphs of cellulose, for example quantifying the proportions of cellulose Iα and Iβ allomorphs in the crystalline domains of various native celluloses. While marine invertebrate animals known as tunicates produce nearly pure cellulose Iβ, solid-state NMR reveals that bacterial cellulose is dominated by the Iα allomorph, but also has additional signals arising from a secondary crystalline form that are normally attributed to cellulose Iβ. However, in this paper we show that the 13C chemical shifts and correlation patterns in 2D NMR spectra for this secondary crystalline form in bacterial cellulose are not the same as those found in cellulose Iβ spectra reported for tunicate cellulose. In order to reach this conclusion, it was necessary to ensure all spectra were correctly set to the same chemical shift scale. In doing so, it became apparent there were spectral features for bacterial cellulose that were entirely consistent with previously reported spectra of bacterial cellulose but did not match those of the Iβ allomorph found in tunicate cellulose. Through a careful and detailed analysis of the 1D and 2D NMR spectra of three 13C-enriched bacterial cellulose samples, two sets of correlated 13C chemical shifts for this secondary crystalline form were identified. The fact that these chemical shifts and correlation patterns are different than those of tunicate cellulose suggests that there exists some sort of structural variation from the Iβ allomorph in bacterial cellulose since the 13C NMR spectrum closely resembles, but is not identical to, the 13C spectrum of the Iβ allomorph found in tunicate cellulose. [ABSTRACT FROM AUTHOR]

Bile acids are the main body of enterohepatic circulation in vivo. They have essential functions such as emulsifying fat, bacteriostasis and regulating multiple metabolic pathways as signal molecules. However, the assignments of NMR signals for some lowconcentration bile acids are still needed. This study combined 1D nuclear magnetic resonance (NMR) and 2D NMR techniques including ¹H-¹H correlation spectroscopy (COSY), ¹H-¹H total correlation spectroscopy (TOCSY), ¹H J-resolved spectroscopy (J-Res), ¹H-13C heteronuclear single quantum coherence spectroscopy (HSQC), and ¹H-13C heteronuclear multiple bond correlation spectroscopy (HMBC) to assign the ¹H and 13C signals of six bile acids in aqueous solution at physiological pH (~7.4) and nine bile acids in methanol. These data are of importance to the NMR-based studies on lipid digestion, absorption, and metabolism. [ABSTRACT FROM AUTHOR]

A one-pot protocol was developed to prepare new thiazol-2(3H)-imines in efficient yields. Therefore, the reaction of the appropriate aromatic amine, phenyl isothiocyanate and chloroacetone (ratio 1:1:1) was mediated using different solvents and bases. The optimized protocol was to conduct the reaction in ethanol at reflux in the presence of 1.2 equivalents of sodium acetate. The reaction produced the regioisomeric (Z)-N-aryl-3-phenylthiazol-2(3H)-imine, as detected by 1D and 2D NMR spectral data. Using a similar protocol, new arene- or chromene-linked thiazol-2(3H)-imines were prepared by the use of the respective α-bromoketones. The new products were screened against six different bacterial strains. In general, chromene-linked thiazol-2(3H)-imines displayed superior antibacterial activity over other products. Thiazol-2(3H)-imines linked to 6-methyl and 6-methoxy-2-oxo-2H-chromene units had the most effective antibacterial activity with MIC/MBC values of 2.0/4.0 and 1.9/3.9 µM, respectively, against Staphylococcus aureus, Streptococcus mutans, and Escherichia coli strains. [ABSTRACT FROM AUTHOR]

In order to improve the reliability of two-dimensional nuclear magnetic resonance (2D NMR) measurement in shale oil reservoirs, the T2-T1 2D NMR response characteristics and influencing factors of shale oil reservoirs were analyzed in three scenarios: laboratory core analysis, wellsite mobile full-diameter core scanning and logging. For different application scenarios, the optimization method of T2-T1 NMR measurement parameters for shale oil reservoirs were proposed. Laboratory core measurements require attention to the choice of echo interval time (TE) and number of echo groups, in addition to the different magnetic field strengths and measurement sequences. When scanning full-diameter cores at the well site, it is necessary to focus on TE and minimum waiting time (Tw). To ensure the convergence in T1 dimension of quickly relaxed component, the minimum Tw should be set to at least 1 ms. NMR logging is limited by the acquisition conditions. It is necessary to focus on the distribution range and smoothing factor in data processing to interpret and modify data with different signal-to-noise ratios. A poor shale oil reservoir with NMR porosity less than 5% is difficult to ensure the accuracy of NMR results for its low signal-to-noise ratio. The systematic analysis of T2-T1 2D NMR measurement parameters provides a reference for the optimization of 2D NMR detection methods for shale oil reservoirs, which helps to improve the accuracy of NMR measurements and obtain more reliable reservoir information.

The content of unfrozen water in the freezing process of coal body affects the microscopic pore structure and macroscopic mechanical properties of coal body and determines the permeability-enhancement effect of coal seam and the extraction efficiency of coal mine gas. To investigate the evolution mechanism of unfrozen water content in the melting process of lignite, this paper takes the melting process of lignite liquid nitrogen after freezing for 150 min as the research object and quantifies the spatial change process of unfrozen water distribution based on two-dimensional nuclear magnetic resonance technology. Through the accurate interpretation of the superimposed signals of different fluids, the 2D NMR technique can more easily obtain the spatial distribution of different fluids and even the specific content of fluids in different pores in coals. The results show that at −196 °C, the unfrozen water mainly existed in the small coal pore and the small ice pore in the large pore. As the temperature rose, the pores melted, and free water began to be produced. The mathematical model analysis shows that there was intermolecular potential energy between fluid molecules and the coal pore wall, and the pore wall exerted a part of pressure on its internal fluid, and the pressure affected the melting point of pore ice with pore diameter and melting temperature, resulting in the difference of unfrozen water content.

ABSTRACTThe clinical efficacy and safety of protein-based drugs such as monoclonal antibodies (mAbs) rely on the integrity of the protein higher order structure (HOS) during product development, manufacturing, storage, and patient administration. As mAb-based drugs are becoming more prevalent in the treatment of many illnesses, the need to establish metrics for quality attributes of mAb therapeutics through high-resolution techniques is also becoming evident. To this end, here we used a forced degradation method, time-dependent oxidation by hydrogen peroxide, on the model biotherapeutic NISTmAb and evaluated the effects on HOS with orthogonal analytical methods and a functional assay. To monitor the oxidation process, the experimental workflow involved incubation of NISTmAb with hydrogen peroxide in a benchtop nuclear magnetic resonance spectrometer (NMR) that followed the reaction kinetics, in real-time through the water proton transverse relaxation rate R2(1H2O). Aliquots taken at defined time points were further analyzed by high-field 2D 1H-13C methyl correlation fingerprint spectra in parallel with other analytical techniques, including thermal unfolding, size-exclusion chromatography, and surface plasmon resonance, to assess changes in stability, heterogeneity, and binding affinities. The complementary measurement outputs from the different techniques demonstrate the utility of combining NMR with other analytical tools to monitor oxidation kinetics and extract the resulting structural changes in mAbs that are functionally relevant, allowing rigorous assessment of HOS attributes relevant to the efficacy and safety of mAb-based drug products.

In this study, we subjected 5,5-diethoxy-4-oxopent-2-enal (DOPE), a model amino acids cross-linking reagent, to reactions with N-acetylcysteine (Ac-Cys) and Nα-acetyllysine (Ac-Lys), and identified three pyrrole cross-links. The compounds were isolated and their structures were rigorously determined by spectrometric and spectroscopic methods, including 2D NMR experiments. The use of 2D NMR spectroscopy was crucial to determine the position of the substituents in the pyrrole rings. The products were identified as 2,4-, 2,3-, and 2,5-substituted pyrroles. The data obtained from their structural characterisation can help similar studies on amino acids modifications induced by analogous bifunctional carbonyl compounds. Our results show that the study of pathways in which model electrophiles modify amino acids may be helpful for similar studies dealing with identification of structural changes in cysteine- and lysine-containing proteins associated with oxidative stress. [ABSTRACT FROM AUTHOR]

Although one can trace the roots of proteomics well back into the 20th century, it is basically a discipline of the new millennium. At its outset, it was defined primarily by the technology available to analyze complex mixtures (basically 2D-gel electrophoresis, hybridizations/arrays and mass spectrometry) and what mainly set it aside from protein chemistry, that had flourished since the end of the second world war, was this use of unfractionated starting material as opposed to homogenous samples. Early on, two major new insights were quickly revealed: that the protein complement of cells was overwhelmingly involved in multiple protein–protein interactions and that it was nearly universally involved in a myriad of post-translational modifications. The revelations of the complex networks that result from these two phenomena have created a new understanding of cell biology that has affected our appreciation of such processes as transcription and translation, transmembrane signaling, differentiation, homeostasis and cell death. The development of these methods and strategies that principally characterize the field of proteomics depended heavily on the evolution of those that advanced protein chemistry, particularly during the last half of the twentieth century leading up to the elucidation of the human genome and will be briefly summarized in this article. In the last five decades of the 20th century, the original tools of protein chemistry combined and evolved to form the powerful largely mass spectrometry-based technology known as proteomics. This, together with the burgeoning science of genomics, has allowed the sensitive identification of proteins in complex samples, the principal targets of proteomics, including protein–protein interactions and post-translational modifications and their intricate roles in functional health and disease. [ABSTRACT FROM AUTHOR]

Microorganisms are an important source of compounds that are pharmaceutically active, both as leads and as scaffolds for synthesis. Often, interesting chemistry is uncovered by exploring new biomes, of which the Chilean Atacama Desert is a prime example. This paper describes the isolation and structural characterisation, using HR-LCMS and 1D and 2D NMR, of a new compound belonging to a family of compounds called radstrictins. The compound was isolated from a fungus, that had itself been isolated from a soil sample from the Atacama Desert. The compound was tested against pathogenic strains associated with bovine mastitis, but was found to be devoid of antimicrobial activity. [ABSTRACT FROM AUTHOR]

From the n‐butanol soluble fraction of the ethanol extract of the medicinal plant Olax subscorpioidea, a previously unreported rotameric biflavonoid glycoside constituted of 4′‐O‐methylgallocatechin‐(4α → 8)‐4′‐O‐methylgallocatechin as aglycone named olasubscorpioside C (1) along with the known 4′‐O‐methylgallocatechin (2) were isolated. Their structures were determined on the basis of spectrometric and spectroscopic techniques including HRFABMS, 1H and 13C NMR, DEPT 135o, HSQC, HMBC, ROESY, and CD followed by comparison with the reported data. [ABSTRACT FROM AUTHOR]

Lignin is considered a promising renewable source of valuable chemical compounds and a feedstock for the production of various materials. Its suitability for certain directions of processing is determined by the chemical structure of its macromolecules. Its formation depends on botanical origin, isolation procedure and other factors. Due to the complexity of the chemical composition, revealing the structural differences between lignins of various origins is a challenging task and requires the use of the most informative methods for obtaining and processing data. In the present study, a combination of two-dimensional nuclear magnetic resonance (2D NMR) spectroscopy and multivariate analysis of heteronuclear single quantum coherence (HSQC) spectra is proposed. Principal component analysis and hierarchical cluster analysis techniques demonstrated the possibility to effectively classify lignins at the level of belonging to classes and families of plants, and in some cases individual species, with an error rate for data classification of 2.3%. The reverse transformation of loading plots into the corresponding HSQC loading spectra allowed for structural information to be obtained about the latent components of lignins and their structural fragments (biomarkers) responsible for certain differences. As a result of the analysis of 34 coniferous, deciduous, and herbaceous lignins, 10 groups of key substructures were established. In addition to syringyl, guaiacyl, and p-hydroxyphenyl monomeric units, they include various terminal substructures: dihydroconiferyl alcohol, balanopholin, cinnamic acids, and tricin. It was shown that, in some cases, the substructures formed during the partial destruction of biopolymer macromolecules also have a significant effect on the classification of lignins of various origins. [ABSTRACT FROM AUTHOR]

We present single- and multiple-quantum correlation J-spectroscopy detected in zero (

Two forms were found in the NMR spectra of N6-substituted 2-chloroadenosines. The proportion of the mini-form was 11–32% of the main form. It was characterized by a separate set of signals in COSY, 15N-HMBC and other NMR spectra. We assumed that the mini-form arises due to the formation of an intramolecular hydrogen bond between the N7 atom of purine and the N6–CH proton of the substituent. The 1H,15N-HMBC spectrum confirmed the presence of a hydrogen bond in the mini-form of the nucleoside and its absence in the main form. Compounds incapable of forming such a hydrogen bond were synthesized. In these compounds, either the N7 atom of the purine or the N6–CH proton of the substituent was absent. The mini-form was not found in the NMR spectra of these nucleosides, confirming the importance of the intramolecular hydrogen bond in its formation. [ABSTRACT FROM AUTHOR]

The 2D NMR (T1-T2) mapping technique, which can be used to separate different proton populations from various sources (hydroxyls, solid organic matter, free water, and free HC) has gained attention in petroleum industry. To separate proton contributions, a fixed straight line is commonly employed to separate different regions representing proton sources on the map. However, some of these regions (Region 1 and 2) might overlap which makes extracting the NMR signal amplitude from these regions inaccurate. In order to solve this issue, in this study, we applied the Gaussian distribution deconvolution method to separate the T1 and T2 relaxation distributions and then derived the signal amplitude of each region instead of following the common fixed line approach. Next, we employed this method to analyze several shale samples from the literature and compared the results following both methods to verify our methodology. Finally, samples from the Bakken Shale were studied to separate signals from Region 1 and Region 2 and correlated the results with geochemical properties that were obtained from programmed (Rock Eval) pyrolysis. Results demonstrated an improvement in their relation when our approach is employed compared to the fixed line technique to differentiate signal from overlapping regions. This means the Gaussian distribution deconvolution method can be used with confidence to provide us with more accurate petrophysical and geochemical understanding of complex formations. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) and their chemical derivatives are well-known as effective carriers for low-water-soluble molecules for pharmaceutical and other industrial applications. We have carried out the synthesis of PEGylated β-CDs through ether chemical bond linkage between β-CD and poly(ethylene glycol) methyl ether (MPEG). The combination of β-CD with poly(ethylene glycol) will benefit from PEG's properties including high water solubility, nontoxicity, non-immunogenicity, biocompatibility, and biodegradability. The synthesis proceeded through three steps: (a) tosylation of MPEG; (b) deprotonation of hydroxyl groups of β-CD using NaH; and (c) the combination of the above two intermediates through the SN2 mechanism to obtain the MPEG-β-CD compounds. The products were confirmed by MALDI-TOF mass spectrometry, and their structures were analyzed using 1H 2D COSY and ROESY NMR methods. It was found that the site of PEGylation occurred on the (OH)6 site of β-CD. The inclusion property of the MPEG-β-CDs was demonstrated by forming inclusion complexes with 1-fluroroadamantane. We anticipate that the newly added properties of the MPEG to β-CD promote their pharmaceutical and other industrial applications. [ABSTRACT FROM AUTHOR]

Introduction: Natural products and metabolomics are intrinsically linked through efforts to analyze complex mixtures for compound annotation. Although most studies that aim for compound identification in mixtures use MS as the main analysis technique, NMR has complementary advances that are worth exploring for enhanced structural confidence. Objective: This review aimed to showcase a portfolio of the main tools available for compound identification using NMR. Materials and Methods: COLMAR, SMART‐NMR, MADByTE, and NMRfilter are presented using examples collected from real samples from the perspective of a natural product chemist. Data are also made available through Zenodo so that readers can test each case presented here. Conclusion: The acquisition of 1H NMR, HSQC, TOCSY, HSQC‐TOCSY, and HMBC data for all samples and fractions from a natural products study is strongly suggested. The same is valid for MS analysis to create a bridged analysis between both techniques in a complementary manner. The use of NOAH supersequences has also been suggested and demonstrated to save NMR time. This review highlights the tools available for compound identification using NMR in natural product chemistry. The tools discussed include COLMAR, SMART‐NMR, MADByTE, and NMRfilter, and examples are presented using real samples. The acquisition of various NMR data, such as 1H NMR, HSQC, TOCSY, HSQC‐TOCSY, and HMBC data, is strongly recommended for natural product studies. The use of NOAH supersequences is also suggested to save NMR time, and an example is provided to demonstrate this. [ABSTRACT FROM AUTHOR]

A survey of the literature reporting solid-state 13C NMR spectra of native celluloses reveals inconsistencies in the reported 13C chemical shifts for cellulose Iα and Iβ allomorphs. With reported chemical shifts varying by up to 2 ppm, it is not clear what the correct chemical shifts actually are. Since reliable experimental data are important to future work, such as quantum chemical calculations of NMR parameters or identification of cellulose phases in complex cellulosic materials, it is important that the correct experimental chemical shifts be established with confidence. Through a process of digitization of previously reported spectra and careful consideration of how chemical shifts were referenced in the past, it has been possible to correct previously reported spectra of cellulose Iα and Iβ, putting them on the same chemical shift scale and establishing a definitive set of correctly referenced 13C chemical shifts for cellulose Iα and Iβ allomorphs. In addition, 1D and 2D 13C NMR experiments were carried out on a cellulose Iα-rich bacterial cellulose sample (with 25% 13C enrichment), providing additional evidence for these 13C chemical shifts and a new peak assignment of the 13C signals to the glucose units in cellulose Iα. This work resolves many of inconsistencies in the cellulose solid-state NMR literature and provides a definitive set of 13C chemical shifts that will be important for future work. [ABSTRACT FROM AUTHOR]

The phenanthrene bromide product mixture obtained from bromination of 9-bromophenanthrene 1, which could not be separated chromatographically, was converted to chromatographically separable methoxy products (3a-d) with CuI catalyzed methoxylation reaction. The resulting products were purified by chromatographic method and detailed structure analysis of the products was done by NMR spectroscopy. Twodimensional NMR spectroscopy methods can be used successfully to elucidate the structures of methoxyphenanthrene derivatives. With the combination of APT, DEPT 90, HETCOR, HMBC, COESY and NOESY spectral data, the position of the substituents was easily determined. In particular, the HMBC and NOESY spectra provide critical information about the positions of the bounded groups. Further bromination reactions of 1,9-dimethoxide 3a selectively gave brominated compound 4. [ABSTRACT FROM AUTHOR]

The dual inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) is considered as an important strategy for the treatment of Alzheimer's disease. In this study, we applied the bioguided fractionations of Ocotea daphinifolia ethyl acetate active extract to furnish a fraction with high inhibitory activity for AChE and BuChE (82% and 92%, respectively). High‐performance liquid chromatography semipreparative purification of this fraction provided two new natural products: 1‐β‐D‐galactopyranosyl‐glycerol‐2,3‐heptanedionate, (1) whose complete chemical structural elucidation was made with spectrometric analysis (MS, 1D, and 2D NMR) and its minor derivative 1‐β‐D‐gulopyranosyl‐glycerol‐2,3‐heptanedionate; (2) which could be characterized by 2D 1H‐13C heteronuclear single‐quantum correlation spectra analysis. Investigation of the intermolecular interactions with cholinesterases was carried out by molecular docking studies, and results suggested that both compounds are capable to interact with the catalytic site of both enzymes. Compounds 1 and 2 interact with residues of catalytic domains and the peripheral anionic binding site of AChE and BuChE. The results are comparable to those achieved with rivastigmine and galantamine. Thus, this study provides evidence for consideration of the glycosylglycerol from O. daphnifolia as new valuable dual cholinesterases inhibitor. [ABSTRACT FROM AUTHOR]

Microorganisms are an important source of compounds that are pharmaceutically active, both as leads and as scaffolds for synthesis. Often, interesting chemistry is uncovered by exploring new biomes, of which the Chilean Atacama Desert is a prime example. This paper describes the isolation and structural characterisation, using HR-LCMS and 1D and 2D NMR, of a new compound belonging to a family of compounds called radstrictins. The compound was isolated from a fungus, that had itself been isolated from a soil sample from the Atacama Desert. The compound was tested against pathogenic strains associated with bovine mastitis, but was found to be devoid of antimicrobial activity.

The paper describes the pyrolytic transformation of hydrolysis lignin in 1,4-dioxane at a temperature of 250°C and a pressure of 13.0 MPa and the subsequent Ru/C-catalyzed hydrogenation of the products at a temperature of 250°C and a pressure of 10.0 MPa in an autoclave. It has been found that the thermal pyrolysis of hydrolysis lignin with 1,4-dioxane and the catalytic hydrogenation of pyrolysis products are accompanied by C−O and C−C bond cleavage and formation of a products mixture consisting of soluble oligomer and monomer phenol derivatives, products of their hydrogenolysis and hydrogenation, and also mixtures of C1−C5 gas hydrocarbons and C2−C5 alcohols, and ethers formed mainly during the destruction of the solvent (1,4-dioxane) under the reaction conditions. [ABSTRACT FROM AUTHOR]

The characterization of residual structures persistent in unfolded proteins is an important issue in studies of protein folding, because the residual structures present, if any, may form a folding initiation site and guide the subsequent folding reactions. Here, we studied the residual structures of the isolated B domain (BDPA) of staphylococcal protein A in 6 M guanidinium chloride. BDPA is a small three‐helix‐bundle protein, and until recently its folding/unfolding reaction has been treated as a simple two‐state process between the native and the fully unfolded states. We employed a dimethylsulfoxide (DMSO)‐quenched hydrogen/deuterium (H/D)‐exchange 2D NMR techniques with the use of spin desalting columns, which allowed us to investigate the H/D‐exchange behavior of individually identified peptide amide (NH) protons. We obtained H/D‐exchange protection factors of the 21 NH protons that form an α‐helical hydrogen bond in the native structure, and the majority of these NH protons were significantly protected with a protection factor of 2.0–5.2 in 6 M guanidinium chloride, strongly suggesting that these weakly protected NH protons form much stronger hydrogen bonds under native folding conditions. The results can be used to deduce the structure of an early folding intermediate, when such an intermediate is shown by other methods. Among three native helical regions, the third helix in the C‐terminal side was highly protected and stabilized by side‐chain salt bridges, probably acting as the folding initiation site of BDPA. The present results are discussed in relation to previous experimental and computational findings on the folding mechanisms of BDPA. [ABSTRACT FROM AUTHOR]

The ability to monitor the dynamics of stem cell differentiation is a major goal for understanding biochemical evolution pathways. Automating the process of metabolic profiling using 2D NMR helps us to understand the various differentiation behaviors of stem cells, and therefore sheds light on the cellular pathways of development, and enhances our understanding of best practices for in vitro differentiation to guide cellular therapies. In this work, the dynamic evolution of adipose-tissue-derived human Mesenchymal stem cells (AT-derived hMSCs) after fourteen days of cultivation, adipocyte and osteocyte differentiation, was inspected based on 1H-1H TOCSY using machine learning. Multi-class classification in addition to the novelty detection of metabolites was established based on a control hMSC sample after four days' cultivation and we successively detected the changes of metabolites in differentiated MSCs following a set of 1H-1H TOCSY experiments. The classifiers Kernel Null Foley-Sammon Transform and Kernel Density Estimation achieved a total classification error between 0% and 3.6% and false positive and false negative rates of 0%. This approach was successfully able to automatically reveal metabolic changes that accompanied MSC cellular evolution starting from their undifferentiated status to their prolonged cultivation and differentiation into adipocytes and osteocytes using machine learning supporting the research in the field of metabolic pathways of stem cell differentiation. [ABSTRACT FROM AUTHOR]

For several millennia, leaves of Echium amoenum Fisch. & C. A. Mey., an important Iranian medicinal plant with nutritional value as nutraceutical, have been used as tea for the treatment of several conditions, including inflammation. The nutritional value of intake of E. amoenum tea has mainly been correlated to its rich content of mainly water-soluble antioxidants. Although the entire plant is utilized, only natural products of the flowers have previously been thoroughly investigated. The rare natural products bis(3-(3,4-dihydroxyphenyl)-1-methoxy-1-oxopropan-2-yl)-1-(3,4-dihydroxyphenyl)-6,7-dihydroxy-1,2-dihydronaphthalene-2,3-dicarboxylate, 4-Oxy-(E)-caffeoyl-2,3-dihydroxybutanoic acid methyl ester and 4-Oxy-(Z)-caffeoyl-2,3-dihydroxybutanoic acid methyl ester, in addition to the widely distributed compounds rosmarinic acid methyl ester and (E)-caffeic acid, were purified and characterized from leaves of Echium amoenum. The structures were determined by a combination of several 2D NMR spectroscopic techniques, circular dichroism spectroscopy and high-resolution mass spectrometry. The fact that bis(3-(3,4-dihydroxyphenyl)-1-methoxy-1-oxopropan-2-yl)-1-(3,4-dihydroxyphenyl)-6,7-dihydroxy-1,2-dihydronaphthalene-2,3-dicarboxylate belongs to a rare group of natural products which have previously been patented for their significant anti-inflammatory activity may rationalize the traditional treatment of inflammations with E. amoenum. [ABSTRACT FROM AUTHOR]

Two-dimensional nuclear magnetic resonance (NMR) technology can perform non-destructive, rapid and quantitative measurement and characterization of various hydrogen-containing fluids in the reservoir, but is limited by the acquisition methods and parameters of NMR equipment. In the detection of samples with ultra-fast relaxation components such as organic matter and asphalt, the problem of missing or inaccurate fluid components in two-dimensional spectrum due to incomplete signal acquisition often occurs. In this paper, a high-precision inversion method of T2-T1 two-dimensional spectrum based on ultrafast relaxation component compensation technology is proposed. This method extends the one-dimensional NMR front-end signal compensation technology. By compensating the components of the echo data before the inversion of two-dimensional NMR data, the problem of signal leakage at the front end of two-dimensional NMR logging can be effectively solved. The application of experiments and logging data shows that this method can obtain more accurate and complete reservoir information in shale oil and other reservoirs rich in signals of fast relaxation components.

• Structures of reaction products between sulfolane cis - or trans -amino alcohols and aromatic aldehydes were defined • New sulfolane hydroxyimines were synthesized and characterized by 1D/2D NMR and X-ray techniques • cis -Imines in the CDCl 3 solution exist in equilibrium with two cyclic tautomers, while the corresponding trans -imines are not able to similar tautomeric transformations. The introduction of electron withdrawing substituents in the benzene ring, contributes to the increase of the content of cyclic (1,3-oxazolidine) forms • It was shown that in DMSO- d 6 solution equilibrium hydroxyimine-oxazolidine shifted towards hydroxyimine in time • Pharmacological profile of the products was evaluated in silico using ADMETlab 2.0 and SwissADME software Cyclic sulfones and their derivatives have vast applications in biological, pharmaceutical, medicinal and in many other fields. Herein, we report synthesis of ten new hydroxyimines bearing sulfolane moiety by reaction of cis - and trans -amino alcohols with aromatic aldehydes. An extensive spectroscopic characterization of the products, using 1D and 2D NMR techniques (1H, 13C, NOE, NOESY, COSY, HSQC, HMBC) showed ring-chain tautomerism in deuterochloroform solution for cis -hydroxyimines. The content of the cyclic (1,3-oxazolidine) form increases with increasing electron-withdrawing strength of the substituent in the para position of the benzene ring of the imine. The structure of cis -(3 S ,4 R)-3-hydroxy-4-((E)-(2-hydroxybenzylidene)amino)tetrahydrothiophene 1,1-dioxide was confirmed using XRD analysis. In addition, ADMET properties of products were evaluated in silico and showed high drug similarity. [Display omitted] [ABSTRACT FROM AUTHOR]

Lavandula angustifolia Mill. is a traditional Chinese medicinal herb with high economic and pharmacological value. In this study, we optimized the conditions for low-temperature ultrasound-assisted extraction of L. angustifolia Mill. polysaccharides using response surface methodology (RSM), and two homopolysaccharides LAP W 1 (33.6 kDa) and LAP S 1 (95.9 kDa) were obtained after isolation and purification by DEAE-650 M and Superdex™ 200 chromatography. The primary structure of LAP S 1 was determined using "partial acid hydrolysis, methylation, two-dimensional (2D NMR) spectroscopy" as the core method. The results revealed that LAP S 1 is a heteropolysaccharide whose main chain consists of [-1)-β-Gal p -(6→1)-α-Ara f -(5→] 3 -1-α-Ara f -(3→1)-α-Ara f -(5→[1)-β-Gal p -(6→1)-α-Ara f -(5→] 3 -1-α-Ara f -(5→1)-α-Ara f -(5→[-1)-β-Gal p -(6→1)-α-Ara f -(5→] 3. In vitro experiments revealed that LAP W 1 and LAP S 1 significantly reduced the production of the inflammatory cytokines Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Tumor Necrosis Factor (TNF), as well as the expression of Nitric Oxide Synthase 2 (NOS2) and release of nitric oxide (.NO) free radical in the inflammatory model established by lipopolysaccharide (LPS) stimulated RAW264.7. Besides, the zebrafish inflammatory model, stimulated by CuSO 4 , was employed to assess the impact of polysaccharides on neutrophil migration, indicating a notable decrease in zebrafish neutrophils and confirming their potential anti-inflammatory activity. These results indicate that polysaccharides from L. angustifolia Mill. be used in the development of functional foods and pharmaceutical products. • Low-temperature ultrasound-assisted extraction was an ideal method to extract L. angustifolia Mill. polysaccharide. • Two novel homogenic polysaccharides LAP S 1 and LAP W 1 were obtained. • The primary structure of LAP S 1 was determined by "Partial Hydrolysis-Methylation-2D NMR" methods. • Both fractions exhibited significant anti-inflammatory activity in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

Metabolomics has been widely applied in human diseases and environmental science to study the systematic changes of metabolites over diverse types of stimuli. NMR-based metabolomics has been widely used, but the peak overlap problems in the one-dimensional (1D) NMR spectrum could limit the accuracy of quantitative analysis for metabolomics applications. Two-dimensional (2D) NMR has been applied to solve the 1D NMR overlap problem, but the data processing is still challenging. In this study, we built an automatic approach to process the 2D NMR data for quantitative applications using machine learning approaches. Partial least square discriminant analysis (PLS-DA), artificial neural network classification (ANN-DA), gradient boosted trees classification (XGBoost-DA), and artificial deep learning neural network classification (ANNDL-DA) were applied in combination with an automatic peak selection approach. Standard mixtures, sea anemone extracts, and mouse fecal samples were tested to demonstrate the approach. Our results showed that ANN-DA and ANNDL-DA have high accuracy in selecting 2D NMR peaks (around 90 %), which have a high potential application in 2D NMR-based metabolomics quantitively study, while PLS-DA and XGBoost-DA showed limitations in either data variation or overfitting. Our study built an automatic approach to applying 2D NMR data to routine quantitative analysis in metabolomics. [Display omitted] • An automatic approach was built for the 2D NMR data quantitative analysis. • Four machine learning approaches were tested for different types of samples. • Artificial deep learning neural network classification showed promising results. • The study paved the road to apply 2D NMR data to routine metabolomics studies. [ABSTRACT FROM AUTHOR]

• Solvent-based free radical grafting of PHBV confirmed and quantified via NMR spectroscopy up to 5.8 mol% of monomer units. • The grafted PHBV exhibited a depression in melting temperature and changes in crystallisation behaviour, potentially widening the processing window. • Some grafted products showed less severe molecular weight reductions compared to similar chemistries observed previously. This study investigates the solvent-based free-radical graft copolymerization of poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) with C 11 (undecenoic acid, UDA), C 12 (dodecene, DD), and C 18 (octadecene, OD) alkene substrates using dicumyl peroxide as an initiator. Comprehensive Nuclear Magnetic Resonance (NMR) spectroscopy was employed to confirm and quantify grafting, which was achieved at up to 5.8 mol% of monomer units. Thermal analysis revealed a significant reduction in melting temperature for all modified PHBVs, ranging from 10-20°C decrease in comparison to virgin PHBV. A decrease in crystallisation temperature and a reduction in glass transition temperature was measured for the UDA and DD grafted PHBV. Additionally, molecular weight analysis showed a marked decrease in weight average molecular weight (M ¯ w) and number average molecular weight (M ¯ n) for PHBV grafted with UDA, which was attributed to the presence of carboxylic acid functionality, which accelerates chain scission. The molecular weight profiles of the dodecene and octadecene grafted PHBV were only marginally reduced (32% and 18% reductions in M ¯ w , respectively), which is a much less severe reduction than has been previously observed for similar chemistries. Overall, this work demonstrates that solvent-based free-radical graft copolymerization can reduce the melting temperature and disrupt the crystallinity of PHBV, hence improving its processability and progressing the field of PHA modification and application. [ABSTRACT FROM AUTHOR]

From the root barks of a Central African tree Millettia dubia De Wild. (Fabaceae), ten previously undescribed oleanane-type glycosides were isolated by various chromatographic protocols. Their structures were elucidated by spectroscopic methods, mainly 2D NMR experiments and mass spectrometry, as mono- and bidesmosidic glycosides of mesembryanthemoidigenic acid, hederagenin and oleanolic acid. The stimulation of the sweet taste receptor TAS1R2/TAS1R3 by these glycosides was evaluated, and structure/activity relationships were proposed. Two of them showed an agonist effect on TAS1R2/TAS1R3. [Display omitted] • Ten different oleanolic acid glycosides were isolated. • Their structures were elucidated by extensive 2D NMR analyses. • The stimulation of the sweet taste receptors TAS1R2/TAS1R3 was evaluated. • Some structure/activity relationships were discussed. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (mAbs) comprise an essential type of biologic therapeutics and are used to treat diseases because of their anti-cancer and anti-inflammatory properties, and their ability to protect against respiratory infections. Its production involves post-translational glycosylation, a biosynthetic process that conjugates glycans to proteins, which plays crucial roles in mAb bioactivities including effector functions and pharmacokinetics. These glycans are heterogeneous and have diverse chemical structures whose composition is sensitive to manufacturing conditions, rendering the understanding of how specific glycan structures affect mAb bioactivity challenging. There is a need to delineate the effects of specific glycans on mAb bioactivity to determine whether changes in certain glycosylation profiles (that can occur during manufacturing) will significantly affect product quality. Using enzymatic transglycosylation with chemically-defined N-glycans, we show that galactosylation at a specific location of N-glycans in an afucosylated anti-viral mAb is responsible for FcγRIIIA binding and antibody-dependent cell-mediated cytotoxicity (ADCC) activity. We report a facile method to obtain purified asymmetric mono-galactosylated biantennary complex N-glycans, and their influence on bioactivity upon incorporation into an afucosylated mAb. Using ELISA, surface plasmon resonance and flow cytometry, we show that galactosylation of the α6 antenna, but not the α3 antenna, consistently increases FcγRIIIA binding affinity. We confirm its relevance in an anti-viral model of respiratory syncytial virus (RSV) using an adapted ADCC reporter assay. We further correlate this structure-function relationship to the interaction of the galactose residue of the α6 antenna with the protein backbone using 2D-1H-15N-NMR, which showed that galactosylation of at this location exhibited chemical shift perturbations compared to glycoforms lacking this galactose residue. Our results highlight the importance of identifying and quantifying specific glycan isomers to ensure adequate quality control in batch-to-batch and biosimilar comparisons.

Isosorbide‐based renewable semi‐fluorinated polymers were synthesized via base‐mediated step‐growth polycondensation of isosorbide diol monomer with bis‐trifluorovinyl ether (TFVE) monomer in excellent yields. As the first example employing secondary alcohols in this addition/elimination polymerization affording fluorinated arylene vinylene ether (FAVE) polymers, reasonable to high‐molecular weights (10–84 kDa) and reproducible glass transition temperatures (Tg) ranging from 120 to 130°C were achieved. Containing 23–31 wt.% renewable isosorbide repeat unit, the amorphous polymers are processable in common organic solvents and form tough, transparent films. Depending on basic conditions, these renewable semi‐fluorinated polymers contain reactive fluoroalkene enchainment for post‐polymerization functionalization and further retain the ability to thermally crosslink without the need for catalysts or initiators. Structural characterization of this complex asymmetric polymer was determined by multi‐nuclear NMR including multiple 2D‐NMR techniques. Renewable FAVE chemistry based on isosorbide presents an intriguing option for alternative renewable materials containing fluorine. [ABSTRACT FROM AUTHOR]

Scrophulariae Radix (SR) is one of the oldest and most frequently used Chinese herbs for oriental medicine in China. Before clinical use, the SR should be processed using different methods after harvest, such as steaming, "sweating", and traditional fire-drying. In order to investigate the difference in chemical constituents using different processing methods, the two-dimensional (2D) 1H-13C heteronuclear single quantum correlation (1H-13C HSQC)-based metabolomics approach was applied to extensively characterize the difference in the chemical components in the extracts of SR processed using different processing methods. In total, 20 compounds were identified as potential chemical markers that changed significantly with different steaming durations. Seven compounds can be used as potential chemical markers to differentiate processing by sweating, hot-air drying, and steaming for 4 h. These findings could elucidate the change of chemical constituents of the processed SR and provide a guide for the processing. In addition, our protocol may represent a general approach to characterizing chemical compounds of traditional Chinese medicine (TCM) and therefore might be considered as a promising approach to exploring the scientific basis of traditional processing of TCM. [ABSTRACT FROM AUTHOR]

5,10,15,20-Tetraphenylporphyrin-copper(II) complex when nitrated with 25% aqueous nitric acid in CHCl3 led to three β,β-substituted dinitro-isomers. One of the structures of products reported in the original paper was assigned incorrectly (as 2,8-dinitro-5,10,15,20-tetraphenylporphyrin derivative). Investigations using high-resolution NMR allowed to assign this compound (examined as demetallated free base) a different structure: 2,13-dinitro-5,10,15,20-tetraphenylporphyrin. These types of products, being practically unavailable by alternative methods, are attractive starting material for synthesis of more complex porphyrinoid moieties. [ABSTRACT FROM AUTHOR]

Sixteen oleanane-type glycosides were extracted from three Weigela hybrids and cultivars: W. x Styriaca, W. florida "Minor black" and W. florida "Brigela", and four of them were previously undescribed ones: 3- O -β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→3)-α- L -rhamnopyranosyl-(1→2)-β- D -xylopyranosyloleanolic acid, 3- O -β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→3)-α- L -rhamnopyranosyl-(1→2)-α- L -arabinopyranosyloleanolic acid, 3- O -β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→3)-α- L -rhamnopyranosyl-(1→2)-α- L -arabinopyranosyloleanolic acid, and 3- O -β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→4)-β- D -xylopyranosyl-(1→3)-α- L -rhamnopyranosyl-(1→2)-α- L -arabinopyranosyloleanolic acid. Their full structural elucidation required extensive 1D and 2D NMR experiments, as well as mass spectrometry analysis. Six compounds among the known ones were in sufficient amount to be tested for their antifungal activity against Candida albicans, and their antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. [Display omitted] • Sixteen saponins were isolated, among which four new. • Their structures were elucidated by extensive spectroscopic analyses. • The chemotaxonomy of the Weigela genus was discussed, based on the structure of the isolated glycosides. • Five of the isolated compounds were tested against Candida albicans , Staphylococcus aureus and Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

Ophiocordyceps sinensis is widely used to treat various diseases and as a health supplement. The present study comprehensively compared the metabolic differences between wild and cultivated O. sinensis through 2D 1H-13C HSQC-based metabolomics, and assessed their anti-lung cancer activity on A549 cells. To characterize the global metabolic profile, sample preparation was scrutinously optimized, and both polar (1:4 methanol-water) and non-polar (1:4 methanol-chloroform) extracts of O. sinensis were investigated. A total of 47 and 10 metabolites were identified in the polar and non-polar extracts, respectively. Principal Component Analysis (PCA) revealed greater differences between the two types of O. sinensis in the polar extracts than in the non-polar extracts. Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) together with univariate tests captured 23 and 19 differential spectral features (with 22 and 11 of them assigned) between wild and cultivated O. sinensis in the polar and non-polar extracts, respectively. Meanwhile, the anti-lung cancer activities of both polar and non-polar extracts of wild and cultivated O. sinensis were assessed by MTS assay on A549 cells, and the sterols found in non-polar extracts, such as ergosterol, ergosterol peroxide, and 9,11-dehydroergosterol peroxide, and β-sitosterol, are the active ingredients with potential anti-lung cancer properties. In this study, we introduced a comprehensive strategy integrating 2D NMR-based metabolomics with in vitro assays for comparing the chemical composition and assessing the pharmacological activity of wild and cultivated O. sinensis. Our results provided a scientific basis for the potential viability of cultivated O. sinensis as an alternative to the wild counterpart. [Display omitted] • Metabolic differences between wild and cultivated O. sinensis were compared. • The anti-lung cancer activity of different O. sinensis extracts was assessed. • 23 and 19 differential features were identified in the polar and non-polar extracts. • Non-polar extracts of wild O. sinensis showed the highest anti-lung cancer activity. [ABSTRACT FROM AUTHOR]

As a non-destructive, efficient and non-invasive detection method, nuclear magnetic resonance (NMR) technology has always played an important role in the analysis of oil and gas cores, but the traditional nuclear magnetic resonance detection results (T2 spectrum) only reflect the size distribution characteristics of rock pores, while the connectivity of pores cannot be directly characterized. Through the improvement of experimental procedures and data processing methods of the standard nuclear magnetic T2 spectrum, the capillary pressure dimension is added in to obtain the T2-Pc two-dimensional nuclear magnetic experiment spectrum, which solves the problem that the nuclear magnetic experiment cannot reflect the pore connectivity. Practical application shows that the T2-Pc two-dimensional nuclear magnetic experiment can not only intuitively evaluate reservoir connectivity, but also obtain bound water saturation under different production pressure differentials, thus providing more reservoir information for oil and gas exploration and development.