Article
Biochemistry & Molecular Biology
Svetlana A. Kondrashova, Fedor M. Polyancev, Shamil K. Latypov
Summary: This study compares calculated and experimental P-31 NMR shifts for a range of palladium complexes and finds that, overall, the theory reproduces the experimental data well. The only exception is complexes with P=O phosphorus, where there is a systematic underestimation of shielding. The use of specific basis sets and polarization functions can reduce this underestimation. In practice, a simple approximation method is acceptable for rapid assessment of P-31 NMR shifts, except for the P=O type. The study also identifies optimal approaches for price-quality ratio. A linear scaling procedure is necessary in all cases to minimize systematic errors.
Article
Chemistry, Physical
Yuriy Yu. Rusakov, Irina L. L. Rusakova
Summary: The basis sets used in quantum chemical calculations of P-31 NMR chemical shifts have a significant impact on their accuracy. Existing basis sets for phosphorus atom lack flexibility in important angular regions, leading to misassignments in P-31 NMR spectra. This study proposes new pecS-n (n = 1, 2) basis sets that demonstrate high accuracy and are useful in large-scale quantum chemical calculations of P-31 NMR chemical shifts.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Manuel Cordova, Martins Balodis, Bruno Simoes de Almeida, Michele Ceriotti, Lyndon Emsley
Summary: This study successfully demonstrates probabilistic chemical shift assignment of organic crystals using a combination of machine learning model and statistical analysis, enabling scientists to assign shifts directly from the structure. The correct assignment was found in over 80% of cases among experimental and predicted shifts.
Article
Chemistry, Organic
William H. Hersh, Tsz-Yeung Chan
Summary: Calculation of 31P NMR chemical shifts for tri-and tetracoordinate phosphorus compounds using different basis sets and DFT functionals showed good fit when plotted against experimental values. The best method varied depending on the structural type and presence of P-C multiple bonds. Failures were observed with widely used functionals, leading to the recommendation of using multiple methods for novel structures.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Environmental Sciences
Diogo Eberhardt, Robelio Marchao, Herve Quiquampoix, Christine Le Guerneve, Volaniaina Ramaroson, Marie Sauvadet, Takashi Muraoka, Thierry Becquer
Summary: This study found that planting companion crops with maize resulted in higher concentrations of available and labile inorganic phosphorus in soil samples, especially with leguminous species. The proportion and amount of P-Orthophosphate increased, while there was a slight increase in P-Monoester content in P-31 NMR analysis. Overall, the proportion of organic P decreased when a legume companion crop was associated with maize.
JOURNAL OF SOILS AND SEDIMENTS
(2021)
Article
Chemistry, Inorganic & Nuclear
Jake A. Thompson, Laia Vila-Nadal
Summary: In this study, the accuracy of various exchange-correlation functionals in reproducing experimental P-31 NMR chemical shifts was systematically investigated using Density Functional Theory (DFT) calculations. The results showed that neutralizing the charge can reduce discrepancies between the calculated and experimental results, but uncertainties still exist for the [B-PW9O34](9-) anion.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Vladimir Palivec, Radek Pohl, Jakub Kaminsky, Hector Martinez-Seara
Summary: Determining the structure of saccharides in their native environment is crucial for understanding their function. In this study, we propose two cost-effective protocols for simulating sugar chemical shifts and recommend their use. These protocols not only help interpret experimental spectra, but can also independently predict structure.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Inorganic & Nuclear
Julius B. Stueckrath, Thomas Gasevic, Markus Bursch, Stefan Grimme
Summary: A new benchmark set SnS51 is proposed for evaluating Sn-119 NMR chemical shifts, covering 51 unique shifts of 50 tin compounds. The study recommends spin-orbit relativistic methods combined with specific functionals to achieve accurate predictions, and an empirical linear scaling correction is suggested for further improvement.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Nigel John Clayden
Summary: NMR chemical shifts play a role in determining protein structure by NMR methods by depending on the local conformation. NMR chemical shielding calculations show that the C alpha H inequivalence in cyclosarcosyls can be rationalized with an appropriate electronic model and basis set. For cyclotetrasarcosyl, although there are significant distant non-bonded effects of a peptide group, the majority of the large inequivalence (>2 ppm) is due to the local conformation between adjacent sarcosine.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Environmental Sciences
Wenqiang Zhang, Rujiang Feng, Xin Meng, Xin Jin, Baoqing Shan
Summary: A new approach for organic phosphorus extraction from freshwater sediments has been developed, optimizing factors such as pH, organic matter, and paramagnetic ions. The study classified sediments based on these factors and determined optimal extraction conditions, leading to higher extraction efficiency. The approach will enhance the use of P-31 NMR for freshwater Po analysis and provide insights into the fate and function of Po in freshwater sediments.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Agriculture, Multidisciplinary
Ping Yu, James W. Marshall, Paul Sadek, Jeffrey H. Walton
Summary: Solid-state magic angle spinning P-31 NMR spectroscopy is used for identification and quantification of phosphorus-containing species in pet foods. The measurement is challenging due to long T (1)s. Data acquisition times are reduced by acquiring data with an angle smaller than 90 degrees and shortening the repetition time. However, different P-31 compounds have different T (1)s, requiring separate measurements for each compound in pet food. Knowledge of T (1) is utilized to calculate the relative amount of P-31 in samples. Samples of known concentration are also measured for quantitative measurement of total phosphorus content.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Markus Bursch, Thomas Gasevic, Julius B. Stueckrath, Stefan Grimme
Summary: A comprehensive benchmark set for calculating Si-29 NMR chemical shifts is presented, including a wide range of silicon-containing compounds in different solvents and bonding patterns. Results show that GGA density functional approximations outperform hybrid approximations, and the inclusion of spin-orbit effects significantly reduces deviations in calculations.
INORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Shuai Wang, Jeffrey D. Sears, Curtis E. Moore, Arnold L. Rheingold, Michael L. Neidig, Joshua S. Figueroa
Summary: The diagonal relationship between phosphorus and carbon in the periodic table suggests that the diatomic diphosphorus molecule (P-2) should have similar properties to acetylene (HC CH). In this study, a mononuclear iron complex featuring P-2 coordination was isolated and characterized, revealing similar electronic demands but different reactivity profiles compared to acetylene coordination.
Article
Automation & Control Systems
Tomas R. Cotos-Yanez, Ana Perez-Gonzalez, Beatriz Iglesias, Luis Munoz
Summary: The article presents an improved statistical approach for estimating the conformational composition of small molecules with low standard error and good p-values.
CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS
(2021)
Article
Chemistry, Multidisciplinary
Fabio P. Calo, Giovanni Bistoni, Alexander A. Auer, Markus Leutzsch, Alois Fuerstner
Summary: The H(C)Rh triple resonance NMR experiment allows for rapid detection of Rh-103 chemical shifts, providing insight into important complexes for metal-carbene chemistry. The excellent agreement between experimental and computed Rh-103 shifts, along with a detailed analysis of shielding tensors, forms a solid foundation for qualitative and quantitative interpretation of previously inaccessible data. Trends observed reflect the influence of equatorial ligands, axial ligands, and internal metalloligand on the electronic properties of the reactive Rh(II) center.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Valentin A. Semenov, Leonid B. Krivdin
Summary: Based on the calculations of NMR chemical shifts, several spectral reassignments and corrections were made to the H-1 and C-13 NMR spectra of the large trimeric indole alkaloid strychnohexamine. New assignments of diastereotopic protons were made and the chemical shifts of unassigned carbon and protons were predicted.
MAGNETIC RESONANCE IN CHEMISTRY
(2021)
Review
Chemistry, Inorganic & Nuclear
Lyudmila I. Larina
Summary: This review discusses the stereochemical structure of functionalized azoles and related compounds obtained by NMR spectroscopy and quantum chemistry, highlighting the importance of understanding their chemical behavior and biological activity.
Article
Chemistry, Multidisciplinary
Ekaterina A. Verochkina, Nadezhda V. Vchislo, Lyudmila Larina, Evgenii A. Titov
Summary: Previously unknown derivatives of thiosemicarbazide were successfully synthesized by condensation reaction, and their corresponding complexes with copper (II) chloride were also obtained. The compounds showed good solubility and significant biological activity. The preliminary screening for acute toxicity indicated that the studied compounds have a low risk of toxicity.
IZVESTIYA VUZOV-PRIKLADNAYA KHIMIYA I BIOTEKHNOLOGIYA
(2022)
Article
Chemistry, Multidisciplinary
Elena Chirkina, Lyudmila Larina
Summary: Derivatives of 1,2,4-triazole exhibit various activities, and understanding the reaction mechanism can help control the chemical synthesis process. Quantum chemical simulation can reveal information about the elementary stages of the reaction, intermediate compounds, and transition states.
STRUCTURAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Lyudmila I. Larina, Alexander I. Albanov, Stanislav N. Zelinskiy, Vadim V. Annenkov, Irina L. Rusakova
Summary: Substituted acrylamides are widely used in organic and medical chemistry, and understanding their electronic structure, spectral properties, and stereochemical transformations is crucial. The structure and stereodynamic behavior of these compounds were studied using dynamic and multinuclear NMR spectroscopy. The results show that acrylamides exist in solution as Z- and E-isomers, with the E-isomer being more prevalent. The experimental values obtained for the activation energy of the isomers range from 15-17 kcal/mol, depending on the stereochemical structure.
MAGNETIC RESONANCE IN CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Valentin A. Semenov, Leonid B. Krivdin
Summary: Succeeding variants of SARS-CoV-2 have increased contagion. Inhibiting the binding of spike protein to the ACE2 receptor is a potential strategy to prevent COVID-19 infection. By using pharmacophore models and induced fit docking, natural compounds that could serve as inhibitors were identified. These findings will stimulate further research and drug development.
Review
Biochemistry & Molecular Biology
Lyudmila Larina
Summary: This review provides extensive data on the stereochemical structure of functionalized organophosphorus azoles and related compounds using multinuclear NMR spectroscopy and quantum chemistry. The most convenient and reliable approach to studying the phosphorus atoms and evaluating the Z/E isomerization is through P-31 NMR spectroscopy combined with high-level quantum-chemical calculations.
Article
Biochemistry & Molecular Biology
Valentin A. Semenov, Leonid B. Krivdin
Summary: H-1 and C-13 NMR chemical shifts of alasmontamine A, a tetracyclic monoterpene indole alkaloid with a molecular formula of C84H91N8O12, were calculated using DFT framework. Six lowest energy conformers and three key configurations contributing to NMR shielding constants were identified. Ambiguities in the reported assignment of NMR chemical shifts of alasmontamine A were resolved.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Organic
V. G. Fedoseeva, E. A. Verochkina, L. I. Larina, N. V. Vchislo
Summary: The condensation of 2-alkylsulfanyl-substituted 2-en-4-ynals with N,N- and N,O-binucleophiles results in the formation of the corresponding 1,3-perhydrodiazines, 1,3-imidazolidines, and 1,3-oxazolidines, maintaining the original combination of substituents.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Dmitry O. O. Samultsev, Valentin A. A. Semenov, Leonid B. B. Krivdin
Summary: The relativistic effects on the shielding constants of various nuclei and their importance in theoretical calculations of chelate complexes were studied. The accuracy factors affecting the calculation of chemical shifts were analyzed. It was found that relativistic effects have a significant impact on the results.
Review
Biochemistry & Molecular Biology
Lyudmila Larina
Summary: The review provides extensive data on the structure of C- and N-chlorophosphorylated enamines and related heterocycles obtained by multipulse multinuclear NMR spectroscopy. The use of phosphorus pentachloride enables the synthesis of various C- and N-phosphorylated products, forming promising nitrogen- and phosphorus-containing heterocyclic systems. P-31 NMR spectroscopy is a convenient and reliable method for studying organophosphorus compounds and determining their coordination numbers and isomeric forms. Alteration of the coordination number of the phosphorus atom in the phosphorylated compounds leads to a significant shift in the P-31 resonance.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Physical
Mikhail V. Andreev, Vladimir A. Potapov, Maxim V. Musalov, Lyudmila I. Larina
Summary: An efficient method for synthesizing a novel family of (Z)-3-amino-3-oxo-1-propenyl selenocyanates was developed using KSeCN and 3-trimethylsilyl-2-propynamides in the presence of ammonium chloride. The reaction involved desilylation and exhibited regio- and stereoselective anti-addition to yield vinyl selenocyanates with a (Z)-configuration in high yields. The absence of ammonium chloride prevented the formation of the desired products.
Article
Chemistry, Physical
Mikhail V. Andreev, Vladimir A. Potapov, Maxim V. Musalov, Lyudmila I. Larina
Summary: The first examples of reactions of 3-trimethylsilyl-2-propynamides with organic diselenides were reported, leading to the synthesis of 3-alkylselanyl-2-propenamides and 3-organylselanyl-2-propynamides. The reactions showed good regio- and stereoselectivity with high yields. Additionally, unsymmetrical divinyl selenides with cyclic amide groups and a product containing multiple selanyl-2-propenamide moieties were synthesized.
Article
Chemistry, Inorganic & Nuclear
Vladimir A. Potapov, Mikhail V. Andreev, Maxim V. Musalov, Irina V. Sterkhova, Svetlana V. Amosova, Lyudmila I. Larina
Summary: The efficient syntheses of novel compounds, (Z,Z)-bis(3-amino-3-oxo-1-propenyl) selenides and diselenides, were achieved via nucleophilic addition reactions. The obtained diselenides showed superior glutathione peroxidase-like activity compared to selenides with the same substituents. Structural analysis through X-ray diffraction and Se-77-NMR data confirmed the structures of the products.
Article
Chemistry, Organic
Kseniya O. Khrapova, Anton A. Telezhkin, Pavel A. Volkov, Lyudmila I. Larina, Dmitry V. Pavlov, Nina K. Gusarova, Boris A. Trofimov
Summary: The reaction between secondary phosphine chalcogenides and primary amino alcohols can selectively deliver amides of chalcogenophosphinic acids under mild conditions, while in a similar reaction, mono-cross-coupling with aminophenols only occurs with the participation of phenolic hydroxyl to give aminophenylchalcogenophosphinic O-esters. The yields of the synthesized functional amides or esters are between 60-85%.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
