Search Results - "Semenov, Valentin A"

DFT computational schemes for 1H and 13C NMR chemical shifts of natural products, exemplified by strychnine by Semenov, Valentin A., Krivdin, Leonid B.

“…A number of computational schemes based on different Density Functional Theory (DFT) functionals in combination with a number of basis sets were tested in the…”
Get full text

Stereochemical Study of the Super Large Tetrakis Alkaloid Alasmontamine A by Means of an Advanced Computational NMR by Semenov, Valentin A, Krivdin, Leonid B

“…H and C NMR chemical shifts of the tetrakis monoterpene indole alkaloid alasmontamine A, with a molecular formula of C H N O , have been calculated within the…”
Get full text

Quelling the Geometry Factor Effect in Quantum Chemical Calculations of 13C NMR Chemical Shifts with the Aid of the pecG-n (n = 1, 2) Basis Sets by Rusakov, Yuriy Yu, Semenov, Valentin A., Rusakova, Irina L.

“…A root factor for the accuracy of all quantum chemical calculations of nuclear magnetic resonance (NMR) chemical shifts is the quality of the molecular…”
Get full text

The Development of Pharmacophore Models for the Search of New Natural Inhibitors of SARS-CoV-2 Spike RBD-ACE2 Binding Interface by Semenov, Valentin A, Krivdin, Leonid B

“…To date, some succeeding variants of SARS-CoV-2 have become more contagious. This virus is known to enter human cells by binding the receptor-binding domain…”
Get full text

On the Efficiency of the Density Functional Theory (DFT)-Based Computational Protocol for 1H and 13C Nuclear Magnetic Resonance (NMR) Chemical Shifts of Natural Products: Studying the Accuracy of the pecS-n (n = 1, 2) Basis Sets by Rusakov, Yuriy Yu, Semenov, Valentin A., Rusakova, Irina L.

“…The basis set issue has always been one of the most important factors of accuracy in the quantum chemical calculations of NMR chemical shifts. In a previous…”
Get full text

Computational NMR Study of Benzothienoquinoline Heterohelicenes by Semenov, Valentin A, Martin, Gary E, Krivdin, Leonid B

“…Early NMR studies of several heterohelicenes containing an annular nitrogen atom and a thiophene ring in their structure suggested the possibility of the…”
Get full text

Four-Component Relativistic Calculations of NMR Shielding Constants of the Transition Metal Complexes—Part 2: Nitrogen-Coordinated Complexes of Cobalt by Samultsev, Dmitry O., Semenov, Valentin A., Rusakova, Irina L., Krivdin, Leonid B.

“…Both four-component relativistic and nonrelativistic computations within the GIAO-DFT(PBE0) formalism have been carried out for 15N and 59Co NMR shielding…”
Get full text

Four-Component Relativistic Calculations of NMR Shielding Constants of the Transition Metal Complexes—Part 3: Fe, Co, Ni, Pd, and Pt Glycinates by Samultsev, Dmitry O., Semenov, Valentin A., Krivdin, Leonid B.

“…The relativistic effects of the values of the shielding constants of 1H, 13C, 15N, 57Fe, 59Co, 61Ni, 105Pd, and 195Pt nuclei were studied at the four-component…”
Get full text

On the accuracy factors and computational cost of the GIAO–DFT calculation of 15N NMR chemical shifts of amides by Samultsev, Dmitry O., Semenov, Valentin A., Krivdin, Leonid B.

“…The main factors affecting the accuracy and computational cost of Gauge‐independent Atomic Orbital–density functional theory (GIAO–DFT) calculation of 15N NMR…”
Get full text

Stereochemical and Computational NMR Survey of 1,2,3-Triazoles: in Search of the Original Tauto-Conformers by Semenov, Valentin A., Larina, Lyudmila I.

“…The conformational analysis of nine functionalized 1,2,3-triazoles was carried out by the correlation of calculated and experimental high-level nuclear…”
Get full text

Theoretical and experimental study of 15N NMR protonation shifts by Semenov, Valentin A., Samultsev, Dmitry O., Krivdin, Leonid B.

“…A combined theoretical and experimental study revealed that the nature of the upfield (shielding) protonation effect in 15N NMR originates in the change of the…”
Get full text

Combined Computational NMR and Molecular Docking Scrutiny of Potential Natural SARS-CoV‑2 Mpro Inhibitors by Semenov, Valentin A, Krivdin, Leonid B

“…In continuation of the search for potential drugs that inhibit the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in this work, a combined…”
Get full text

Simple and Versatile Scheme for the Stereochemical Identification of Natural Products and Diverse Organic Compounds with Multiple Asymmetric Centers by Semenov, Valentin A, Krivdin, Leonid B

“…A simple and versatile scheme of stereochemical identification of the stereochemically rich natural products and organic compounds with multiple asymmetric…”
Get full text

Combined Computational NMR and Molecular Docking Scrutiny of Potential Natural SARS-CoV-2 M pro Inhibitors by Semenov, Valentin A, Krivdin, Leonid B

“…In continuation of the search for potential drugs that inhibit the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in this work, a combined…”
Get full text

Computational 1H and 13C NMR of the trimeric monoterpenoid indole alkaloid strychnohexamine: Selected spectral updates by Semenov, Valentin A., Krivdin, Leonid B.

“…Very large trimeric indole alkaloid strychnohexamine, with empirical formula C59H60N6O (66 second‐row atoms and 60 protons), has been subjected to the…”
Get full text

Benchmark density functional theory calculations of 13C NMR chemical shifts of the natural antimalarial compounds with a new basis set 3z‐S by Semenov, Valentin A., Krivdin, Leonid B.

“…The PBE0 functional in combination with a new highly economical triple zeta basis set 3z‐S was applied for the benchmark calculations of 13C NMR chemical…”
Get full text

Computational NMR of natural products: On the way to super large molecules exemplified with alasmontamine A by Semenov, Valentin A., Krivdin, Leonid B.

“…1H and 13C nuclear magnetic resonance (NMR) chemical shifts of a tetrakis monoterpene indole alkaloid alasmontamine A with a molecular formula of C84H91N8O12…”
Get full text

Reactions of α‑Functionally Substituted Enals with Terminal Alkynes: Unexpected Assembly of 2‑Amino-2-Cyclopentenones by Shnigirev, Rustam B., Ushakov, Igor A., Semenov, Valentin A., Rulev, Alexander Yu

“…The reactions of α-chalcogen, α-halo, or α-amino functionally substituted enals with terminal alkynes leading either to corresponding propargyl alcohols (for…”
Get full text

1H and 13C NMR spectra of Strychnos alkaloids: Selected NMR updates by Semenov, Valentin A., Samultsev, Dmitry O., Krivdin, Leonid B.

“…The PBE0/pcSseg‐2//pcseg‐2 calculations of 1H and 13C NMR chemical shifts were performed for a classical series of 12 Strychnos alkaloids (except for the…”
Get full text

Computational studies of [1]benzothieno[2,3‐c]naphtho[1,2‐f]quinoline by Semenov, Valentin A., Martin, Gary E., Krivdin, Leonid B.

“…Early NMR studies of several heterohelicenes containing an annular nitrogen atom and a thiophene ring in their structure suggested the possibility of the…”
Get full text