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Journal articles on the topic 'NMR spectral methods'

Author: Grafiati

Published: 5 June 2025

Last updated: 1 August 2025

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1

Li, Da-Wei, Lei Bruschweiler-Li, Alexandar L. Hansen, and Rafael Brüschweiler. "DEEP Picker1D and Voigt Fitter1D: a versatile tool set for the automated quantitative spectral deconvolution of complex 1D-NMR spectra." Magnetic Resonance 4, no. 1 (2023): 19–26. http://dx.doi.org/10.5194/mr-4-19-2023.

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Abstract. The quantitative deconvolution of 1D-NMR spectra into individual resonances or peaks is a key step in many modern NMR workflows as it critically affects downstream analysis and interpretation. Depending on the complexity of the NMR spectrum, spectral deconvolution can be a notable challenge. Based on the recent deep neural network DEEP Picker and Voigt Fitter for 2D NMR spectral deconvolution, we present here an accurate, fully automated solution for 1D-NMR spectral analysis, including peak picking, fitting, and reconstruction. The method is demonstrated for complex 1D solution NMR s

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2

Jaipuria, Garima, Adil Hayat, and Hanudatta S. Atreya. "New methods for NMR spectral analysis." Journal of Analytical Science and Technology 2, Supplement A (2011): A88—A93. http://dx.doi.org/10.5355/jast.2011.a88.

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3

Belton, Peter S., and Kevin M. Wright. "Constrained deconvolution methods for NMR spectral enhancement." Journal of Magnetic Resonance (1969) 68, no. 3 (1986): 564–67. http://dx.doi.org/10.1016/0022-2364(86)90348-3.

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4

Eshimbetov, Alisher, Shahobiddin Adizov, Inderpreet Kaur, and Akhmed Reymov. "Is it possible to differentiate between 2-phenylaminodihydro-1,3-thiazine from 2-phenyliminotetrahydro-1,3-thiazine by spectral methods? New glance to the old problem." European Journal of Chemistry 12, no. 1 (2021): 77–80. http://dx.doi.org/10.5155/eurjchem.12.1.77-80.2068.

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Several studies have reported the presence of amine and imine tautomeric forms for hydrogenated 1,3-thiazine derivatives. However, identification of their tautomeric forms by UV, FTIR and mass-spectral methods does not yield expected results. Here, we report the synthesis of 2-phenylaminodihydro-1,3-thiazine and 2-phenyliminotetrahydro-1,3-thiazine and the analysis of their UV, FTIR and NMR (1H and 13C) spectral data. An identical picture of UV spectra was recorded for both compounds. However, distinctive characteristics were found in the FTIR, 1H and 13C NMR spectra. The C=N band of amine for

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5

Nakai, T., R. Ishima, H. Sakahara, K. Endo, J. Konishi, and K. Akasaka. "An in vitro1H-MRS Model of Oncogene Transfection." Acta Radiologica 38, no. 6 (1997): 1083–86. http://dx.doi.org/10.1080/02841859709172136.

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Purpose: Malignancy is an abnormality of cell division and differentiation based on abnormal expression of oncogenes. This note describes the in vitro1H-NMR spectral features of oncogene-transfected NIH3T3 fibroblast cells compared to non-transfected cells Material and Methods: 1H-NMR spectra of cultured NIH3T3 cells and c-erbB-2 or c-Ha-ras gene-transfected cells were obtained by 400 MHz high resolution NMR. the peaks were assigned by 2D HOHAHA spectra of the cell suspension and the spectral changes were evaluated in 1D and 1D differential spectra Results: the 1H spectra obtained from both tr

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6

R., Jeyaraman, C. Thenmozhiyal J., Murugadoss R., and Muthukumar M. "Stereodynamics of diheteroarylpiperidines and their derivatives." Journal of Indian Chemical Society Vol. 76, Nov-Dec 1999 (1999): 527–36. https://doi.org/10.5281/zenodo.5861764.

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Department of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India <em>Manuscript received 10 August 1999</em> The stereodynamics of a number of <em>N</em>-nitroso-<em>cis</em>-<em>r</em>-2,<em>c</em>-6-di(2-hctcroaryl)- and <em>N</em>-nitroso-<em>cis</em>-<em>r</em>-2,<em>c</em>-6-diarylpiperidines (12-17) have been studied. The conformational preferences have been correlated with those of <em>N</em>-nitroso-<em>cis</em>-<em>r</em>-2,<em>c</em>-6-dimethylpiperidine (1) and <em>N</em>-nitroso-<em>cis</em>-<em>r</em>-2,<em>c</em>-6-diphenylpiperidines (2a-f, 3a-e). Competition be

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7

van Beek, Jacco D., Beat H. Meier, and Hartmut Schäfer. "Inverse methods in two-dimensional NMR spectral analysis." Journal of Magnetic Resonance 162, no. 1 (2003): 141–57. http://dx.doi.org/10.1016/s1090-7807(02)00193-3.

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8

Johnson, Hayden, and Aaryani Tipirneni-Sajja. "Neural Networks for Conversion of Simulated NMR Spectra from Low-Field to High-Field for Quantitative Metabolomics." Metabolites 14, no. 12 (2024): 666. https://doi.org/10.3390/metabo14120666.

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Background: The introduction of benchtop NMR instruments has made NMR spectroscopy a more accessible, affordable option for research and industry, but the lower spectral resolution and SNR of a signal acquired on low magnetic field spectrometers may complicate the quantitative analysis of spectra. Methods: In this work, we compare the performance of multiple neural network architectures in the task of converting simulated 100 MHz NMR spectra to 400 MHz with the goal of improving the quality of the low-field spectra for analyte quantification. Multi-layered perceptron networks are also used to

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9

Matukhin V. L., Gavrilenko A. N., Schmidt E. V., et al. "Application of radio spectroscopy methods for the study of thermoelectrics with a chalcopyrite structure." Semiconductors 56, no. 1 (2022): 27. http://dx.doi.org/10.21883/sc.2022.01.53012.23.

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Doped chalcopyrite compounds are considered. The results of studying the spectral parameters by the 63,65Cu NMR method in a local field, as well as by the EPR method in the temperature range 15-300 K are presented. The observed broadening of the resonance lines of the NMR spectra and the detection of a paramagnetic signal in the sample at a temperature of 15 K indicate the appearance of anti-structural defects. The rapid change in the shape of the EPR spectrum line, in the temperature range 100-130 K, is associated with the structural-phase transition. Keywords: thermoelectrics, chalcopyrite c

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10

Matukhin V. L., Gavrilenko A. N., Schmidt E. V., et al. "Application of radio spectroscopy methods for the study of thermoelectrics with a chalcopyrite structure." Semiconductors 56, no. 1 (2022): 21. http://dx.doi.org/10.21883/sc.2022.01.53698.23.

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Doped chalcopyrite compounds are considered. The results of studying the spectral parameters by the 63,65Cu NMR method in a local field, as well as by the EPR method in the temperature range 15-300 K are presented. The observed broadening of the resonance lines of the NMR spectra and the detection of a paramagnetic signal in the sample at a temperature of 15 K indicate the appearance of anti-structural defects. The rapid change in the shape of the EPR spectrum line, in the temperature range 100-130 K, is associated with the structural-phase transition. Keywords: thermoelectrics, chalcopyrite c

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11

Sinha Roy, Aritro, and Madhur Srivastava. "Unsupervised Analysis of Small Molecule Mixtures by Wavelet-Based Super-Resolved NMR." Molecules 28, no. 2 (2023): 792. http://dx.doi.org/10.3390/molecules28020792.

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Resolving small molecule mixtures by nuclear magnetic resonance (NMR) spectroscopy has been of great interest for a long time for its precision, reproducibility, and efficiency. However, spectral analyses for such mixtures are often highly challenging due to overlapping resonance lines and limited chemical shift windows. The existing experimental and theoretical methods to produce shift NMR spectra in dealing with the problem have limited applicability owing to sensitivity issues, inconsistency, and/or the requirement of prior knowledge. Recently, we resolved the problem by decoupling multiple

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12

Gesmar, Henrik, Jens J. Led, and Frits Abildgaard. "Improved methods for quantitative spectral analysis of NMR data." Progress in Nuclear Magnetic Resonance Spectroscopy 22, no. 3 (1990): 255–88. http://dx.doi.org/10.1016/0079-6565(90)80002-y.

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13

Lia, Frederick, Benjamin Vella, Marion Zammit Mangion, and Claude Farrugia. "Application of 1H and 13C NMR Fingerprinting as a Tool for the Authentication of Maltese Extra Virgin Olive Oil." Foods 9, no. 6 (2020): 689. http://dx.doi.org/10.3390/foods9060689.

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The application of 1H and 13C nuclear magnetic resonance (NMR) in conjunction with chemometric methods was applied for the discrimination and authentication of Maltese extra virgin olive oils (EVOOs). A total of 65 extra virgin olive oil samples, consisting of 30 Maltese and 35 foreign samples, were collected and analysed over four harvest seasons between 2013 and 2016. A preliminary examination of 1H NMR spectra using unsupervised principle component analysis (PCA) models revealed no significant clustering reflecting the geographical origin. In comparison, PCA carried out on 13C NMR spectra r

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14

Marinov, Marin. "TWO METHODS FOR 3-AMINOCYCLOPENTANESPIRO-5- HYDANTOIN THIONATION." Journal scientific and applied research 3, no. 1 (2013): 10–14. http://dx.doi.org/10.46687/jsar.v3i1.56.

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This article presents two methods for 3-aminocyclopentanespiro-5-hydantoin thionation. These methods are based on the treatment of the titled compound with P4S10 or Lawesson’s reagent. The corresponding dithio-analogue was synthesized as a result of these interactions. The structure of the product obtained was verified by 1HNMR, 13C NMR and mass spectral data.

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15

Wang, Xinyi, Peter de B. Harrington, and Steven F. Baugh. "Comparative Study of NMR Spectral Profiling for the Characterization and Authentication of Cannabis." Journal of AOAC INTERNATIONAL 100, no. 5 (2017): 1356–64. http://dx.doi.org/10.5740/jaoacint.17-0089.

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Abstract For the authentication of botanical materials, itis difficult to obtain representative reference materials because botanicals vary significantly with respect to cultivation conditions. Chemical profiling of plant extracts or spectral fingerprinting can differentiate botanicals and group them by their chemical profiles. NMR spectroscopy yields a powerful and useful method for profiling plant extracts. Both 500 MHz 1H and 1H-1H correlation NMR spectroscopy coupled with pattern recognition were used to discriminate among Cannabis samples. A rapid method of analysis was achieved by extrac

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16

Hara, Koki, Shunji Yamada, Eisuke Chikayama, and Jun Kikuchi. "Parameter Visualization of Benchtop Nuclear Magnetic Resonance Spectra toward Food Process Monitoring." Processes 10, no. 7 (2022): 1264. http://dx.doi.org/10.3390/pr10071264.

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Low-cost and user-friendly benchtop low-field nuclear magnetic resonance (NMR) spectrometers are typically used to monitor food processes in the food industry. Because of excessive spectral overlap, it is difficult to characterize food mixtures using low-field NMR spectroscopy. In addition, for standard compounds, low-field benchtop NMR data are typically unavailable compared to high-field NMR data, which have been accumulated and are reusable in public databases. This work focused on NMR parameter visualization of the chemical structure and mobility of mixtures and the use of high-field NMR d

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17

Stark, Pauline, Caroline Zab, Andrea Porzel, Katrin Franke, Paride Rizzo, and Ludger A. Wessjohann. "PSYCHE—A Valuable Experiment in Plant NMR-Metabolomics." Molecules 25, no. 21 (2020): 5125. http://dx.doi.org/10.3390/molecules25215125.

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1H-NMR is a very reproducible spectroscopic method and, therefore, a powerful tool for the metabolomic analysis of biological samples. However, due to the high complexity of natural samples, such as plant extracts, the evaluation of spectra is difficult because of signal overlap. The new NMR “Pure Shift” methods improve spectral resolution by suppressing homonuclear coupling and turning multiplets into singlets. The PSYCHE (Pure Shift yielded by Chirp excitation) and the Zangger–Sterk pulse sequence were tested. The parameters of the more suitable PSYCHE experiment were optimized, and the extr

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18

Robinson, Alastair, Peter Richardson, and Meghan Halse. "Hyperpolarised 1H–13C Benchtop NMR Spectroscopy." Applied Sciences 9, no. 6 (2019): 1173. http://dx.doi.org/10.3390/app9061173.

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Benchtop NMR spectrometers with sub-ppm spectral resolution have opened up new opportunities for performing NMR outside of the standard laboratory environment. However, the relatively weak magnetic fields of these devices (1–2 T) results in low sensitivity and significant peak overlap in 1H NMR spectra. Here, we use hyperpolarised 13C{1H} NMR to overcome these challenges. Specifically, we demonstrate the use of the signal amplification by reversible exchange (SABRE) parahydrogen-based hyperpolarisation technique to enhance the sensitivity of natural abundance 1D and 2D 13C{1H} benchtop NMR spe

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19

Enev, V., L. Pospíšilová, M. Klučáková, T. Liptaj, and L. Doskočil. "Spectral characterization of selected humic substances." Soil and Water Research 9, No. 1 (2014): 9–17. http://dx.doi.org/10.17221/39/2013-swr.

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Current concern for soil quality has stimulated research on soil organic matter (OM). Humic substances (HS) of different origin were compared applying ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), &ldquo;steady-state&rdquo; fluorescence spectroscopy, and <sup>13</sup>C nuclear magnetic resonance (<sup>13</sup>C NMR). Sodium humates samples were isolated from soil (Gleyic Luvisol), compost, and South-Moravian lignite from the mine M&iacute;r in Mikulčice. Sodium humates (SH) were extracted by a conventional procedure recomm

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20

Kalyan, K. Mukherjea, and Panda Gourisankar. "Copper(II)-glutathinone (reduced) interaction : assessment of copper-peptide environment by physico-chemical and spectral methods in isolated system." Journal of Indian Chemical Society Vol. 81, Mar 2004 (2004): 210–13. https://doi.org/10.5281/zenodo.5830424.

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Department of Chemistry, Jadavpur University, Kolkata-700 032, India <em>E-mail</em> : k_mukherjea@yahoo.com Fax: 91-33-24146584 <em>Manuscript received 31 January 2003, revised 13 August 2003. accepted 12 September 2003</em> The copper(II)-glutathiune has been synthesized in the aqueous medium and its composition has been determined by elemental analyses and thermogravimetric analyses. FT-IR studies indicate the involvement of amide-I, glutamyl -NH<sub>2</sub>, the COOH group and -SH group in coordination with copper. The binding mode has further been substantiated by <sup>1</sup>H NMR spectr

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21

Ольга Валерьевна, Лусина,, Берестова, Татьяна Вячеславовна, Кузина, Людмила Георгиевна, Лобов, Александр Николаевич, and Мустафин, Ахат Газизьянович. "THE SPECTRAL CHARACTERISTICS OF THE L-CYSTEINE SULFONIC ACID." Вестник Тверского государственного университета. Серия: Химия, no. 3(49) (October 28, 2022): 80–88. http://dx.doi.org/10.26456/vtchem2022.3.10.

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Методами спектроскопии ИК- и ЯМР Н и С с использованием теоретических расчетов (программы ChemDrawUltra, Marvin, ACD/Labs) изучены спектральные характеристики L-цистеинсульфоновой кислоты (L-cysSOH) в растворах в виде частично протонированной формы (SO)CHCH(NH)COO-(рН=3) и депротонированного иона(SO-)CHCH(NH)COO-(рН=10). Установлено, что в отличие от спектров ЯМР Н L-цистеинсульфоновой кислоты, в спектрах ЯМР С не наблюдается сильного смещения химических сдвигов относительно друг друга в зависимости от pH среды, что позволяет провести интерпретацию L-цистеинсульфоновой кислоты в растворе разли

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22

Ngo, Quoc Luan, Phu Thach Nguyen, Van Minh Em Nguyen, et al. "Isolation and identification of triterpenoid compounds from Couroupita guianensis Aubl." Can Tho University Journal of Science 15, no. 1 (2023): 91–97. http://dx.doi.org/10.22144/ctu.jen.2023.012.

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In this report, the extracts from the fruit and leaves of Couroupita guianensis were isolated using chromatographic methods and investigated for chemical composition. Four triterpenoid compounds were isolated and identified as betulinic acid, oleanolic acid, β-amyrin and friedelin. Their chemical structures were interpreted based on modern spectra such as MS, NMR and compared with previously published spectral data.

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23

Manoleras, Nick, and Raymond S. Norton. "Spectral processing methods for the removal of t1 noise and solvent artifacts from NMR spectra." Journal of Biomolecular NMR 2, no. 5 (1992): 485–94. http://dx.doi.org/10.1007/bf02192811.

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24

Sangill, R., N. Rastrupandersen, H. Bildsoe, H. J. Jakobsen, and N. C. Nielsen. "Optimized Spectral Editing of 13C MAS NMR Spectra of Rigid Solids Using Cross-Polarization Methods." Journal of Magnetic Resonance, Series A 107, no. 1 (1994): 67–78. http://dx.doi.org/10.1006/jmra.1994.1048.

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25

Sajed, Tanvir, Zinat Sayeeda, Brian L. Lee, et al. "Accurate Prediction of 1H NMR Chemical Shifts of Small Molecules Using Machine Learning." Metabolites 14, no. 5 (2024): 290. http://dx.doi.org/10.3390/metabo14050290.

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NMR is widely considered the gold standard for organic compound structure determination. As such, NMR is routinely used in organic compound identification, drug metabolite characterization, natural product discovery, and the deconvolution of metabolite mixtures in biofluids (metabolomics and exposomics). In many cases, compound identification by NMR is achieved by matching measured NMR spectra to experimentally collected NMR spectral reference libraries. Unfortunately, the number of available experimental NMR reference spectra, especially for metabolomics, medical diagnostics, or drug-related

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26

Klinot, Jiří, Jiří Rozen, Eva Klinotová та Alois Vystrčil. "A-nor-derivatives of 19β,28-epoxy-18α-oleanane: Preparation and stereochemistry". Collection of Czechoslovak Chemical Communications 52, № 2 (1987): 493–500. http://dx.doi.org/10.1135/cccc19870493.

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19β,28-Epoxy-A(1)-nor-18α-oleanan-3-one (IV) was converted into the A-nor-derivatives V-XII whose structure and configuration was confirmed by chemical reactions and spectral methods. Proton NMR and IR spectra show that the 2α- and 3β-bonds on the five-membered ring A are pseudoaxial whereas the 2β- and 3α-bonds are pseudoequatorial.

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27

Ebbels, Timothy M. D., John C. Lindon, and Jeremy K. Nicholson. "Quantitative Investigation of Probabilistic Spectral Processing Methods Using Simulated NMR Data." Applied Spectroscopy 55, no. 9 (2001): 1214–24. http://dx.doi.org/10.1366/0003702011953225.

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28

GESMAR, H., J. J. LED, and F. ABILDGAARD. "ChemInform Abstract: Improved Methods for Quantitative Spectral Analysis of NMR Data." ChemInform 22, no. 16 (2010): no. http://dx.doi.org/10.1002/chin.199116329.

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29

Zahra, Fatima Tuz, Aamer Saeed, Atteeque Ahmed, Hammad Ismail, Muhammad Umar Ijaz та Fernando Albericio. "Synthesis of amantadine clubbed N-aryl amino thiazoles as potent urease, α-amylase & α-glucosidase inhibitors, kinetic and molecular docking studies". RSC Advances 13, № 36 (2023): 24988–5001. http://dx.doi.org/10.1039/d3ra05330j.

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A series of ten novel compounds were synthesized by incorporating a 1,3 thiazole core into amantadine and their structures were validated using different analytical and spectral methods such as FTIR, EI-MS, 1H NMR, and 13C NMR.

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30

Novotný, Ladislav, Miloš Buděšínský, Josef Jizba, et al. "Configuration of natural 9-hydroxyfuroeremophilane, its 9-hydroxy epimer and furanopetasin: NMR and CD studies." Collection of Czechoslovak Chemical Communications 52, no. 7 (1987): 1786–802. http://dx.doi.org/10.1135/cccc19871786.

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The conformation and configuration analysis of cis- and trans-furoeremophilanes with hydroxy group in position 9, using 1H NMR and CD spectra, is discussed. Some steroid derivatives were used as models for CD study. A combination of both spectral methods gives complementary results. For natural 9-hydroxyfuroeremophilane the configuration 9β-OH was unequivocally proved and the originally proposed structure of furanopetasin corrected to VII.

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31

Yegorova, Tatyana, Bogdan Barnych, and Zoia Voitenko. "Reaction of pyrido[2,1-a]isoindole with 1,4-naphtoquinone and study of the product by spectroscopic methods." French-Ukrainian Journal of Chemistry 4, no. 2 (2016): 33–39. http://dx.doi.org/10.17721/fujcv4i2p33-39.

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Key role of the electronic structure of condensed isoindols in the way of the rearrangement was shown. Influence of the dienophile manifests in the requirement of the cyclic form of the dienophile itself. In the reaction of pyrido[2,1-a]isoindole with naphtoquinone rearrangement product of the first type was obtained and its structure was proven by spectral methods. Spectral criteria for the rearranged adducts of the first type for the pyrido[2,1-a]isoindole in the 13C NMR spectra were established. Products of reactions with naphthoquinone, 4-fluoro-, 2,5-difluorophenylmaleimides were isolated

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32

Veijanen, A., E. Kolehmainen, R. Kauppinen, M. Lahtiperä, and J. Paasivirta. "Methods for the Identification of Tainting Terpenoids and other Compounds from Algae." Water Science and Technology 25, no. 2 (1992): 165–70. http://dx.doi.org/10.2166/wst.1992.0048.

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Off-flavour compounds produced by algae in freshwater ecosystems were studied for their structure using integrated sensory and spectroscopic methods: mass spectrometry (MS), nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR). Both solvent extraction and thermal desorption were used to isolate and to introduce the compounds into gas chromatography/mass spectrometry (GC/MS) and gas chromatography/Fourier transform infrared (GC/FTIR) systems. Ten ng of a terpenoid compound gave a readable IR spectrum. For 1H NMR studies the compounds were collected directly into NMR solvent by

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33

Aljawad, Mohammed Saleh, Abdullah Abdulhasan Ali, and Marwah Dhahir Abdulkhadim. "Comparison of Petrophysical Properties Measurement Methods in Sandston Rocks." Iraqi Journal of Chemical and Petroleum Engineering 19, no. 2 (2018): 15–20. http://dx.doi.org/10.31699/ijcpe.2018.2.3.

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This paper displays a survey about the laboratory routine core analysis study on ten sandstone core samples taken from Zubair Reservoir/West Quarna Oil Field. The Petrophysical properties of rock as porosity, permeability, grain's size, roundness and sorting, type of mineral and volumes of shales inside the samples were tested by many apparatus in the Petroleum Technology Department/ University of Technology such as OFITE BLP-530 Gas Porosimeter, PERG-200TM Gas Permeameter and liquid Permeameter, GeoSpec2 apparatus (NMR method), Scanning Electron Microscopy (SEM) and OFITE Spectral Gamma Ray L

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Bakibaev, A. A., S. Yu Panshina, O. V. Ponomarenko, V. S. Malkov, O. A. Kotelnikov, and A. K. Tashenov. "1D and 2D NMR spectroscopy for identification of carbamide-containing biologically active compounds." Bulletin of the Karaganda University. "Chemistry" series 101, no. 1 (2021): 71–81. http://dx.doi.org/10.31489/2021ch1/71-81.

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Urea (carbamide) is the main end product of amino acids' metabolism in mammals. Extensive research in the field of urea chemistryhas contributed to the creation of many biologically active and other compounds based on the carbamide fragment NH–CO–NH. The substituting groups of urea directly affect its properties and characteristics which are reflected in the NMR spectral data and this circumstance can be the basis for the identification of urea derivatives. In this work, chemical shifts in the NMR spectra of urea and its acyclic structure, barbituric series, imidazolidinone series and bicyclic

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35

Džodić, Jelica, Milica Marković, Dejan Milenković, and Dušan Dimić. "Molecular Aspects of the Interactions between Selected Benzodiazepines and Common Adulterants/Diluents: Forensic Application of Theoretical Chemistry Methods." International Journal of Molecular Sciences 25, no. 18 (2024): 10087. http://dx.doi.org/10.3390/ijms251810087.

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Benzodiazepines are frequently encountered in crime scenes, often mixed with adulterants and diluents, complicating their analysis. This study investigates the interactions between two benzodiazepines, lorazepam (LOR) and alprazolam (ALP), with common adulterants/diluents (paracetamol, caffeine, glucose, and lactose) using infrared (IR) spectroscopy and quantum chemical methods. The crystallographic structures of LOR and ALP were optimized using several functionals (B3LYP, B3LYP-D3BJ, B3PW91, CAM-B3LYP, M05-2X, and M06-2X) combined with the 6-311++G(d,p) basis set. M05-2X was the most accurate

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Rendón, Willy, Galia Chávez, Myriam Meléndez-Rodríguez, and Pedro Joseph-Nathan. "Total assignment of the1H and13C NMR spectra of piperovatine." Spectroscopy 14, no. 1 (1998): 35–40. http://dx.doi.org/10.1155/1998/453785.

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Total and unambiguous assignment of the1H NMR spectrum of piperovatine [6‒(4‒methoxyphenyl)‒N‒(2‒methylpropyl)‒2,4‒hexadienamide] was carried out using conventional 1D NMR methods and spectral spin–spin simulation. Based on these data, the complete assignment of the13C NMR chemical shift values was made by a13C/1H chemical shift correlation diagram and conventional considerations for the quaternary carbon atom.

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Mason, H. E., E. C. Uribe, and J. A. Shusterman. "Rapid acquisition of data dense solid-state CPMG NMR spectral sets using multi-dimensional statistical analysis." Physical Chemistry Chemical Physics 20, no. 26 (2018): 18082–88. http://dx.doi.org/10.1039/c8cp02382d.

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Tensor-rank decomposition methods have been applied to variable contact time <sup>29</sup>Si{<sup>1</sup>H} CP/CPMG NMR data sets to extract NMR dynamics information and dramatically decrease conventional NMR acquisition times.

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Makieieva, Natalina, Teobald Kupka, and Oimahmad Rahmonov. "The Search for the Optimal Methodology for Predicting Fluorinated Cathinone Drugs NMR Chemical Shifts." Molecules 30, no. 1 (2024): 54. https://doi.org/10.3390/molecules30010054.

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Cathinone and its synthetic derivatives belong to organic compounds with narcotic properties. Their structural diversity and massive illegal use create the need to develop new analytical methods for their identification in different matrices. NMR spectroscopy is one of the most versatile methods for identifying the structure of organic substances. However, its use could sometimes be very difficult and time-consuming due to the complexity of NMR spectra, as well as the technical limitations of measurements. In such cases, molecular modeling serves as a good supporting technique for interpreting

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Lin, Yanqin, Qing Zeng, Liangjie Lin, and Zhong Chen. "High Resolution Nuclear Magnetic Resonance Spectroscopy on Biological Tissue and Metabolomics." Current Medicinal Chemistry 26, no. 12 (2019): 2190–207. http://dx.doi.org/10.2174/0929867326666190312130155.

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High-resolution nuclear magnetic resonance (NMR) spectroscopy is a universal analytical tool. It can provide detailed information on chemical shifts, J coupling constants, multiplet patterns, and relative peak areas. It plays an important role in the fields of chemistry, biology, medicine, and pharmacy. A highly homogeneous magnetic field is a prerequisite for excellent spectral resolution. However, in some cases, such as in vivo and ex vivo biological tissues, the magnetic field inhomogeneity due to magnetic susceptibility variation in samples is unavoidable and hard to eliminate by conventio

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Ashbrook, Sharon E., John M. Griffin, and Karen E. Johnston. "Recent Advances in Solid-State Nuclear Magnetic Resonance Spectroscopy." Annual Review of Analytical Chemistry 11, no. 1 (2018): 485–508. http://dx.doi.org/10.1146/annurev-anchem-061417-125852.

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The sensitivity of nuclear magnetic resonance (NMR) spectroscopy to the local atomic-scale environment offers great potential for the characterization of a diverse range of solid materials. Despite offering more information than its solution-state counterpart, solid-state NMR has not yet achieved a similar level of recognition, owing to the anisotropic interactions that broaden the spectral lines and hinder the extraction of structural information. Here, we describe the methods available to improve the resolution of solid-state NMR spectra and the continuing research in this area. We also high

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Sahebalzamani, Hajar, Shahriare Ghammamy, Shaghayegh Dexhkam, Alireza Hemati Moghadam, and Farhod Siavoshifar. "Synthesis, Characterization and Thermal Analysis of a New Acetic Acid (2-Hydroxy-benzylidene)-hydrazide and its Complexes with Hg(II) and Pd(II)." E-Journal of Chemistry 8, s1 (2011): S13—S18. http://dx.doi.org/10.1155/2011/270304.

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The new complexes have been synthesized by the reaction of Hg(II) and Pd(II) with acetic acid(2-hydroxy-benzylidene)- hydrazide (L). These new complexes were characterized by elemental analysis, IR, H NMR spectroscopy and UV spectral techniques. The changes observed between the FT-IR, H NMR and UV-Vis spectra of the ligands and of the complexes allowed us to establish the coordination mode of the metal in complexes. Thermal properties, TG-DTA of these complexes were studied. TG- DTA and other analytical methods have been applied to the investigation of the thermal behavior and structure of the

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Kuz’mina, N. E., S. V. Moiseev, and A. I. Luttseva. "The Problem of Dynamic Process Manifestation in Identification of Organic Compounds by NMR Spectroscopy." Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products 10, no. 1 (2020): 63–76. http://dx.doi.org/10.30895/1991-2919-2020-10-1-63-76.

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The number, shape and position of NMR spectral lines depend on dynamic processes, and this creates certain difficulties in identification of pharmaceutical substances by NMR spectroscopy. The aim of the paper was to study instances of manifestation of intramolecular dynamic processes that affect identification of organic compounds by NMR, and to illustrate the potential of the methods used for their reduction, as well as associated problems.Materials and methods: 1H and 13C spectra of the following pharmaceutical substances: «buserelin acetate», «valsartan», «goserelin acetate», «iopromide», «

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Ogbonda-Chukwu, E., O. J. Abayeh, and O. Achugasim. "Two facile synthetic methods for a Schiff base from 4-ethoxyaniline and 2-pyridinecarboxaldehyde." Scientia Africana 22, no. 1 (2023): 67–74. http://dx.doi.org/10.4314/sa.v22i1.7.

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The Schiff base was acquired from the reaction between 4-ethoxyaniline and 2-pyridinecarboxaldehyde using three (3) synthetic methods: 2 hours reflux in ethanol, stirring in ethanol and in an ethanol-water (1:1 v/v) mixture at ambient temperature for an hour. The synthesis of 4-ethoxyaniline-2-pyridinecarboxaldehyde Schiff base afforded dark-brown crystals with a melting point of 118-120°C. The reflux reaction in ethanol gave the highest yield of 83.5% while the reaction in ethanol and in ethanol-water (1:1 v/v) mixture at ambient temperature gave 73.0% and 43.6% yield respectively. The confir

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Lina, Saadi, and A. Ghali Azhar. "Synthesis and Characterization of Some Metal Complexes Derived from Azo Ligand of 4,4' Methylenedianiline and Resorcinol." Biomedicine and Chemical Sciences 1, no. 4 (2022): 241–48. https://doi.org/10.48112/bcs.v1i4.252.

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The metal complexes of Azo dye; 4,4'-((methylene bis(3,l-phenylen)) bis (diazene-l,2-diyl)) bis(1,3-Benzenediol) are produced from 4,4`- methylenedianiline and Resorcinol were synthesized and characterized by using several analytical and spectral techniques. The ligand and its complexes were characterized by many chemo-physic methods like NMR, IR, UV-Vis, molar conductance measurement, analytical measurement, and melting point. The conditions of optimal reaction  (for instance reagent concentration, pH etc) were studied and the analytical figures of merit such as limit of detection, l

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Moiseev, S. V., N. E. Kuz’mina, E. Yu Severinova, E. P. Simonova та V. V. Kosenko. "Identification and Quantification of the Component Composition of the Active Substance Gentamicin Sulfate by <sup>1</sup>Н and <sup>13</sup>С NMR Spectroscopy". Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products. Regulatory Research and Medicine Evaluation 13, № 2-1 (2023): 283–91. http://dx.doi.org/10.30895/1991-2919-2023-13-2-1-283-291.

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Gentamicin sulfate is a broad-spectrum bactericidal aminoglycoside antibiotic produced by Micromonospora purpurea and used in clinical practice as an active substance containing a mixture of gentamicins C1 and C2. Gentamicin content is a standardised parameter controlled as part of a pharmaceutical product review. Currently, the quality control of the active substance gentamicin sulfate involves the use of high-performance liquid chromatography (HPLC) for the indirect identification of the component composition by comparison with a reference standard and for its quantification by calibration a

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Jackowski, Karol, and Mateusz A. Słowiński. "Searching for the Best Values of NMR Shielding and Spin-Spin Coupling Parameters: CH4-nFn Series of Molecules as the Example." Molecules 28, no. 3 (2023): 1499. http://dx.doi.org/10.3390/molecules28031499.

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Attempts at the theoretical interpretation of NMR spectra have a very long and fascinating history. Present quantum chemical calculations of shielding and indirect spin-spin couplings permit modeling NMR spectra when small, isolated molecules are studied. Similar data are also available from NMR experiments if investigations are performed in the gas phase. An interesting set of molecules is formed when a methane molecule is sequentially substituted by fluorine atoms—CH4-nFn, where n = 0, 1, 2, 3, or 4. The small molecules contain up to three magnetic nuclei, each with a one-half spin number. T

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Jackowski, Karol. "Nuclear Magnetic Resonance Gas-Phase Studies of Spin-Spin Couplings in Molecules." Chemistry 7, no. 1 (2025): 16. https://doi.org/10.3390/chemistry7010016.

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This paper overviews gas phase experiments with respect to one fundamental part of nuclear magnetic resonance (NMR) spectra. Indirect spin-spin coupling is an important parameter of NMR spectra and is observed as the splitting of spectral signals. A molecule containing two different magnetic nuclei (e.g., hydrogen HD, HT, or DT) exhibits this interaction in an external magnetic field measured as the spin-spin coupling parameter, nJ(NN′). Modern quantum chemical methods allow the precise calculation of spin-spin coupling, but it is never easy because nJ(NN′) is modified by temperature and inter

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Boyko, Kristina V., Erin A. Rosenkranz, Derrick M. Smith, et al. "Sortase-mediated segmental labeling: A method for segmental assignment of intrinsically disordered regions in proteins." PLOS ONE 16, no. 10 (2021): e0258531. http://dx.doi.org/10.1371/journal.pone.0258531.

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A significant number of proteins possess sizable intrinsically disordered regions (IDRs). Due to the dynamic nature of IDRs, NMR spectroscopy is often the tool of choice for characterizing these segments. However, the application of NMR to IDRs is often hindered by their instability, spectral overlap and resonance assignment difficulties. Notably, these challenges increase considerably with the size of the IDR. In response to these issues, here we report the use of sortase-mediated ligation (SML) for segmental isotopic labeling of IDR-containing samples. Specifically, we have developed a ligat

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Ludwig, Christian. "MetaboLabPy—An Open-Source Software Package for Metabolomics NMR Data Processing and Metabolic Tracer Data Analysis." Metabolites 15, no. 1 (2025): 48. https://doi.org/10.3390/metabo15010048.

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Introduction: NMR spectroscopy is a powerful technique for studying metabolism, either in metabolomics settings or through tracing with stable isotope-enriched metabolic precursors. MetaboLabPy (version 0.9.66) is a free and open-source software package used to process 1D- and 2D-NMR spectra. The software implements a complete workflow for NMR data pre-processing to prepare a series of 1D-NMR spectra for multi-variate statistical data analysis. This includes a choice of algorithms for automated phase correction, segmental alignment, spectral scaling, variance stabilisation, export to various s

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Pustovalova, Yulia, Frank Delaglio, D. Levi Craft, et al. "NUScon: a community-driven platform for quantitative evaluation of nonuniform sampling in NMR." Magnetic Resonance 2, no. 2 (2021): 843–61. http://dx.doi.org/10.5194/mr-2-843-2021.

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Abstract. Although the concepts of nonuniform sampling (NUS) and non-Fourier spectral reconstruction in multidimensional NMR began to emerge 4 decades ago (Bodenhausen and Ernst, 1981; Barna and Laue, 1987), it is only relatively recently that NUS has become more commonplace. Advantages of NUS include the ability to tailor experiments to reduce data collection time and to improve spectral quality, whether through detection of closely spaced peaks (i.e., “resolution”) or peaks of weak intensity (i.e., “sensitivity”). Wider adoption of these methods is the result of improvements in comput

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