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Funes M, Tosso RD, Machado ND, Fernández MA, Garro M, Díaz DD, Hikawczuk VJ, Enriz RD. Antinociceptive effect of cyclic and linear diterpenoids as new atypical agonists of κ-opioid receptors obtained from four species of the Baccharis genus, and vehiculated in nanometric niosomes. Fitoterapia 2023; 169:105622. [PMID: 37524126 DOI: 10.1016/j.fitote.2023.105622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/24/2023] [Accepted: 07/24/2023] [Indexed: 08/02/2023]
Abstract
New natural analgesic compounds that act in KORs are important alternatives for potential therapeutical use in medicine. In this work, we report and compare here the antinociceptive activity displayed by cyclic and linear diterpenes, obtained from the genus Baccharis. The antinociceptive activities determined were relatively strong, in comparison whit morphine. The antinociceptive mechanism of action was made through naloxone administration (a non-selective antagonist of opioid receptors). The more active compounds were vehiculized successfully in niosomes at nanometric scale. The observed antinociceptive activity for Bartemidiolide oxide (BARTO), obtain from Baccharis artemisioides, was greater than Flabeloic acid dimer (DACD), the first compound isolated from Baccharis flabellata that was reported possessing antinociceptive effects. We also conducted docking calculations and molecular dynamics simulations, which suggested that the newly identified diterpenes might share the molecular action mechanism reported for Salvinorin A (SalA). Molecular simulations have allowed us to appreciate some subtle differences between molecular interactions of these ligands stabilizing their respective complexes; such information might be useful for designing and searching for new inhibitors of KORs.
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Affiliation(s)
- Matías Funes
- Pharmacognosy, School of Chemistry, Biochemistry, and Pharmacy, National University of San Luis, Av. Ejército de los Andes 950, 5700 San Luis, Argentina; Multidisciplinary Institute for Biological Research (IMIBIO-CONICET), Av. Ejército de los Andes 950, 5700 San Luis, Argentina.
| | - Rodrigo D Tosso
- Multidisciplinary Institute for Biological Research (IMIBIO-CONICET), Av. Ejército de los Andes 950, 5700 San Luis, Argentina
| | - Noelia D Machado
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba X5000HUA, Argentina; Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA-UNC-CONICET), Avda. Vélez Sársfield 1611, Córdoba X5016GCA, Argentina
| | - Mariana A Fernández
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba X5000HUA, Argentina; Instituto de Investigaciones en Físico-Química de Córdoba (INFIQC-CONICET), Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - María Garro
- Pharmacognosy, School of Chemistry, Biochemistry, and Pharmacy, National University of San Luis, Av. Ejército de los Andes 950, 5700 San Luis, Argentina
| | - David Díaz Díaz
- Departamento de Química Orgánica, Universidad de la Laguna, La Laguna, Spain; Instituto Universitario de Bio-Orgánica Antonio González, Universidad de la Laguna, La Laguna, Spain; Institute of Organic Chemistry, University of Regensburg, Universitätstr. 31, Regensburg 93053, Germany
| | - Virginia Juan Hikawczuk
- Organic Chemistry, School of Chemistry, Biochemistry, and Pharmacy, National University of San Luis, Av. Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Ricardo D Enriz
- Pharmacognosy, School of Chemistry, Biochemistry, and Pharmacy, National University of San Luis, Av. Ejército de los Andes 950, 5700 San Luis, Argentina; Multidisciplinary Institute for Biological Research (IMIBIO-CONICET), Av. Ejército de los Andes 950, 5700 San Luis, Argentina.
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Gutiérrez LJ, Tosso RD, Zarycz MNC, Enriz RD, Baldoni HA. Epitopes mapped onto SARS-CoV-2 receptor-binding motif by five distinct human neutralising antibodies. Molecular Simulation 2022. [DOI: 10.1080/08927022.2022.2111421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Lucas J. Gutiérrez
- Multidisciplinary Institute of Biological Research (IMIBIO-SL. CONICET), San Luis, Argentina
- Faculty of Chemistry, Biochemistry and Pharmacy, National University of San Luis, San Luis, Argentina
| | - Rodrigo D. Tosso
- Multidisciplinary Institute of Biological Research (IMIBIO-SL. CONICET), San Luis, Argentina
- Faculty of Chemistry, Biochemistry and Pharmacy, National University of San Luis, San Luis, Argentina
| | - M. Natalia C. Zarycz
- Multidisciplinary Institute of Biological Research (IMIBIO-SL. CONICET), San Luis, Argentina
| | - Ricardo D. Enriz
- Multidisciplinary Institute of Biological Research (IMIBIO-SL. CONICET), San Luis, Argentina
- Faculty of Chemistry, Biochemistry and Pharmacy, National University of San Luis, San Luis, Argentina
| | - Héctor A. Baldoni
- Faculty of Chemistry, Biochemistry and Pharmacy, National University of San Luis, San Luis, Argentina
- Institute of Applied Mathematics of San Luis (IMASL. CONICET), San Luis, Argentina
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Tosso RD, Zarycz MNC, Schiel A, Goicoechea Moro L, Baldoni HA, Angelina E, Enriz RD. Evaluating the conformational space of the active site of D 2 dopamine receptor. Scope and limitations of the standard docking methods. J Comput Chem 2022; 43:1298-1312. [PMID: 35638694 DOI: 10.1002/jcc.26938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 04/11/2022] [Accepted: 05/08/2022] [Indexed: 11/05/2022]
Abstract
We report here for the first time the potential energy surfaces (PES) of phenyletilamine (PEA) and meta-tyramine (m-OH-PEA) at the D2 dopamine receptor (D2DR) binding site. PESs not only allow us to observe all the critical points of the surface (minimums, maximums, and transition states), but also to note the ease or difficulty that each local minima have for their conformational inter-conversions and therefore know the conformational flexibility that these ligands have in their active sites. Taking advantage of possessing this valuable information, we analyze how accurate a standard docking study is in these cases. Our results indicate that although we have to be careful in how to carry out this type of study and to consider performing some extra-simulations, docking calculations can be satisfactory. In order to analyze in detail the different molecular interactions that are stabilizing the different ligand-receptor (L-R) complexes, we carried out quantum theory of atoms in molecules (QTAIM) computations and NMR shielding calculations. Although some of these techniques are a bit tedious and require more computational time, our results demonstrate the importance of performing computational simulations using different types of combined techniques (docking/MD/hybrid QM-MM/QTAIM and NMR shielding calculations) in order to obtain more accurate results. Our results allow us to understand in details the molecular interactions stabilizing and destabilizing the different L-R complexes reported here. Thus, the different activities observed for dopamine (DA), m-OH-PEA, and PEA can be clearly explained at molecular level.
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Affiliation(s)
- Rodrigo D Tosso
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas, San Luis, Argentina
| | - M Natalia C Zarycz
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas, San Luis, Argentina
| | - Ayelén Schiel
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas, San Luis, Argentina
| | - Luisa Goicoechea Moro
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas, San Luis, Argentina
| | - Héctor A Baldoni
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis; Instituto de Matemáticas, San Luis, Argentina
| | - Emilio Angelina
- Laboratorio de Estructura Molecular y Propiedades, Facultad de Ciencias Exactas y Naturales y Agrimensura, Universidad Nacional del Nordeste, Instituto de Química Básica y Aplicada, Corrientes, Argentina
| | - Ricardo D Enriz
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas, San Luis, Argentina
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Emam AM, Dahal A, Singh SS, Tosso RD, Ibrahim SM, El-Sadek M, Jois SD, Enriz RD, Kothayer H. Quinazoline-tethered hydrazone: A versatile scaffold toward dual anti-TB and EGFR inhibition activities in NSCLC. Arch Pharm (Weinheim) 2021; 354:e2100281. [PMID: 34585758 DOI: 10.1002/ardp.202100281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 11/07/2022]
Abstract
Globally, lung cancer and tuberculosis are considered to be very serious and complex diseases. Evidence suggests that chronic infection with tuberculosis (TB) can often lead to lung tumors; therefore, developing drugs that target both diseases is of great clinical significance. In our study, we designed and synthesized a suite of 14 new quinazolinones (5a-n) and performed biological investigations of these compounds in Mycobacterium tuberculosis (MTB) and cancer cell lines. In addition, we conducted a molecular modeling study to determine the mechanism of action of these compounds at the molecular level. Compounds that showed anticancer activity in the preliminary screening were further evaluated in three cancer cell lines (A549, Calu-3, and BT-474 cells) and characterized in an epidermal growth factor receptor (EGFR) binding assay. Cytotoxicity in noncancerous lung fibroblast cells was also evaluated to obtain safety data. Our theoretical and experimental studies indicated that our compounds showed a mechanism of action similar to that of erlotinib by inhibiting the EGFR tyrosine kinase. In turn, the antituberculosis activity of these compounds would be produced by the inhibition of enoyl-ACP-reductase. From our findings, we were able to identify two potential lead compounds (5i and 5l) with dual activity and elevated safety toward noncancerous lung fibroblast cells. In addition, our data identified three compounds with excellent anti-TB activities (compounds 5i, 5l, and 5n).
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Affiliation(s)
- Aya M Emam
- Department of Medicinal Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Achyut Dahal
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, Louisiana, USA
| | - Sitanshu S Singh
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, Louisiana, USA
| | - Rodrigo D Tosso
- Pharmacy Department, Facultad de Química, Bioquímica y Farmacia, IMIBIO-CONICET, Universidad Nacional de San Luis, San Luis, Argentina
| | - Samy M Ibrahim
- Department of Medicinal Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Mohamed El-Sadek
- Department of Medicinal Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Seetharama D Jois
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, Louisiana, USA
| | - Ricardo D Enriz
- Pharmacy Department, Facultad de Química, Bioquímica y Farmacia, IMIBIO-CONICET, Universidad Nacional de San Luis, San Luis, Argentina
| | - Hend Kothayer
- Department of Medicinal Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
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Tosso RD, Parravicini O, Zarycz MNC, Angelina E, Vettorazzi M, Peruchena N, Andujar S, Enriz RD. Conformational and electronic study of dopamine interacting with theD2dopamine receptor. J Comput Chem 2020; 41:1898-1911. [DOI: 10.1002/jcc.26361] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/10/2020] [Accepted: 05/22/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Rodrigo D. Tosso
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
| | - Oscar Parravicini
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
| | - M. Natalia C. Zarycz
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
| | - Emilio Angelina
- Laboratorio de Estructura Molecular y PropiedadesFacultad de Ciencias Exactas y Naturales y Agrimensura Corrientes Argentina
- Instituto de Química Básica y Aplicada (IQUIBA‐NEA)CONICET Corrientes Argentina
| | - Marcela Vettorazzi
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
| | - Nélida Peruchena
- Laboratorio de Estructura Molecular y PropiedadesFacultad de Ciencias Exactas y Naturales y Agrimensura Corrientes Argentina
- Instituto de Química Básica y Aplicada (IQUIBA‐NEA)CONICET Corrientes Argentina
| | - Sebastián Andujar
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
| | - Ricardo D. Enriz
- Facultad de Química, Bioquímica y FarmaciaUniversidad Nacional de San Luis San Luis Argentina
- Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO‐SL)CONICET San Luis Argentina
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Aguirre-Pranzoni C, Tosso RD, Bisogno FR, Kurina-Sanz M, Orden AA. Preparation of chiral β-hydroxytriazoles in one-pot chemoenzymatic bioprocesses catalyzed by Rhodotorula mucilaginosa. Process Biochem 2019. [DOI: 10.1016/j.procbio.2018.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Funes M, Garro MF, Tosso RD, Maria AO, Saad JR, Enriz RD. Antinociceptive effect of neo-clerodane diterpenes obtained from Baccharis flabellata. Fitoterapia 2018; 130:94-99. [DOI: 10.1016/j.fitote.2018.08.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/13/2018] [Accepted: 08/22/2018] [Indexed: 10/28/2022]
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Angelina EL, Andujar SA, Tosso RD, Enriz RD, Peruchena NM. Non-covalent interactions in receptor-ligand complexes. A study based on the electron charge density. J PHYS ORG CHEM 2013. [DOI: 10.1002/poc.3250] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Emilio L. Angelina
- Lab. Estructura Molecular y Propiedades, Área de Química Física, Departamento de Química, Facultad de Ciencias Exactas y Naturales y Agrimensura; Universidad Nacional del Nordeste; Av. Libertad 5470 Corrientes 3400 Argentina
- Instituto Multidiciplinario de Investigaciones Biológicas (IMIBIO-SL, CONICET); Chacabuco y Pedrenera (5700) San Luis Argentina
| | - Sebastián A. Andujar
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia; Universidad Nacional de San Luis; Chacabuco 917, San Luis (5700) San Luis Argentina
- Instituto Multidiciplinario de Investigaciones Biológicas (IMIBIO-SL, CONICET); Chacabuco y Pedrenera (5700) San Luis Argentina
| | - Rodrigo D. Tosso
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia; Universidad Nacional de San Luis; Chacabuco 917, San Luis (5700) San Luis Argentina
- Instituto Multidiciplinario de Investigaciones Biológicas (IMIBIO-SL, CONICET); Chacabuco y Pedrenera (5700) San Luis Argentina
| | - Ricardo D. Enriz
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia; Universidad Nacional de San Luis; Chacabuco 917, San Luis (5700) San Luis Argentina
- Instituto Multidiciplinario de Investigaciones Biológicas (IMIBIO-SL, CONICET); Chacabuco y Pedrenera (5700) San Luis Argentina
| | - Nélida M. Peruchena
- Lab. Estructura Molecular y Propiedades, Área de Química Física, Departamento de Química, Facultad de Ciencias Exactas y Naturales y Agrimensura; Universidad Nacional del Nordeste; Av. Libertad 5470 Corrientes 3400 Argentina
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Tosso RD, Andujar SA, Gutierrez L, Angelina E, Rodríguez R, Nogueras M, Baldoni H, Suvire FD, Cobo J, Enriz RD. Molecular modeling study of dihydrofolate reductase inhibitors. Molecular dynamics simulations, quantum mechanical calculations, and experimental corroboration. J Chem Inf Model 2013; 53:2018-32. [PMID: 23834278 DOI: 10.1021/ci400178h] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A molecular modeling study on dihydrofolate reductase (DHFR) inhibitors was carried out. By combining molecular dynamics simulations with semiempirical (PM6), ab initio, and density functional theory (DFT) calculations, a simple and generally applicable procedure to evaluate the binding energies of DHFR inhibitors interacting with the human enzyme is reported here, providing a clear picture of the binding interactions of these ligands from both structural and energetic viewpoints. A reduced model for the binding pocket was used. This approach allows us to perform more accurate quantum mechanical calculations as well as to obtain a detailed electronic analysis using the quantum theory of atoms in molecules (QTAIM) technique. Thus, molecular aspects of the binding interactions between inhibitors and the DHFR are discussed in detail. A significant correlation between binding energies obtained from DFT calculations and experimental IC₅₀ values was obtained, predicting with an acceptable qualitative accuracy the potential inhibitor effect of nonsynthesized compounds. Such correlation was experimentally corroborated synthesizing and testing two new inhibitors reported in this paper.
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Affiliation(s)
- Rodrigo D Tosso
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 917, 5700 San Luis, Argentina
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Andujar SA, Tosso RD, Suvire FD, Angelina E, Peruchena N, Cabedo N, Cortes D, Enriz RD. Searching the "biologically relevant"conformation of dopamine: a computational approach. J Chem Inf Model 2011; 52:99-112. [PMID: 22146008 DOI: 10.1021/ci2004225] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We report here an exhaustive and complete conformational study on the conformational potential energy hypersurface (PEHS) of dopamine (DA) interacting with the dopamine D2 receptor (D2-DR). A reduced 3D model for the binding pocket of the human D2-DR was constructed on the basis of the theoretical model structure of bacteriorhodopsin. In our reduced model system, only 13 amino acids were included to perform the quantum mechanics calculations. To obtain the different complexes of DA/D2-DR, we combined semiempirical (PM6), DFT (B3LYP/6-31G(d)), and QTAIM calculations. The molecular flexibility of DA interacting with the D2-DR was evaluated from potential energy surfaces and potential energy curves. A comparative study between the molecular flexibility of DA in the gas phase and at D2-DR was carried out. In addition, several molecular dynamics simulations were carried out to evaluate the molecular flexibility of the different complexes obtained. Our results allow us to postulate the complexes of type A as the "biologically relevant conformations" of DA. In addition, the theoretical calculations reported here suggested that a mechanistic stepwise process takes place for DA in which the protonated nitrogen group (in any conformation) acts as the anchoring portion, and this process is followed by a rapid rearrangement of the conformation allowing the interaction of the catecholic OH groups.
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Affiliation(s)
- Sebastian A Andujar
- Departamento de Química, Universidad Nacional de San Luis, Chacabuco 915, 5700 San Luis, Argentina
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Tosso RD, Zamora MA, Suvire FD, Enriz RD. Ab initio and DFT study of the conformational energy hypersurface of cyclic Gly-Gly-Gly. J Phys Chem A 2010; 113:10818-25. [PMID: 19754096 DOI: 10.1021/jp905187k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The multidimensional conformational potential energy hypersurface (PEHS) of cyclic Gly-Gly-Gly (1,4,7-triazonane-2,5,8-trione) was comprehensively investigated at the Hartree-Fock (RHF/6-31G(d)) level of theory. The equilibrium structures, their relative stability, and the transition state (TS) structures involved in the conformational interconversion pathways were analyzed. aug-cc-pVTZ//B3LYP/6-311++G** single point calculations predict a trans-cis-cis conformation as the energetically preferred form for this compound. However, all of the levels of theory employed here predicted that two forms, a trans-cis-cis and a cis-cis-cis (crown), of conformers contribute significantly to the equilibrium mixture at room temperature. The conformational interconversion between the global minimum and the symmetric cis-cis-cis crown form requires 12.49 kcal/mol at the RHF 6-31G(d) level of theory, whereas the conformational interconversion between the cis-cis-cis crown and cis-cis-cis boat form requires 18.70 kcal/mol. An exploratory topological analysis of the PEHS was also carried out. Our results allow us to form a concise idea about the internal intricacies of the PEHSs of these cyclic tripeptides, describing the conformations as well as the conformational interconversion processes in these hypersurfaces.
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Affiliation(s)
- Rodrigo D Tosso
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 915, 5700 San Luis, Argentina
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