Conformational investigation of amino acid derivatives and corresponding intramolecular interactions through NMR and IR spectroscopies and theoretical calculations

• Grant number: 12/18567-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2013
• End date: July 31, 2016
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Roberto Rittner Neto
• Grantee: Carolyne Brustolin Braga
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated scholarship(s): 14/18233-4 - Investigating the structural complexity of ancient Australian arthropod venoms, BE.EP.DR

Abstract

It is proposed the conformational analysis of esters and N-acetyl derivatives of some aminoacids as proline, aspartic acid, cysteine and histidine, through NMR spectroscopy (H-1, C-13 and N-15), infrared spectroscopy and theoretical calculations. The theoretical calculations will be performed using the MP2 ab initio method and, also, several functionals of Density Functional Theory (DFT) and several basis sets and icluding the zero point energy correction (ZPE), which are available in the GAUSSIAN-09 package, for the determination of the more stable conformer energies and geometries in the isolated state and with the IEFPCM solvation method to simulate the solvent effects on the conformational isomerism of the proposed compounds. Stretching frequency calculations of the C=O group and J(HX)(X = H, C or N) coupling constants will be used together with experimental data from infrared and NMR spectra, respectively, in several solvents for an evaluation of the number of conformers, their geometries and populations. For the evaluation of molecular interactions of classical origen (steric and electrostatic) and quantum (hyperconjugation) for their conformational stability, the topological analysis through the quantum theory of atoms in molecules (QTAIM) and the natural bond orbitals (NBO) calculations will also be performed. The overall data will allow the evaluation which are the main effects responsible for the conformational equilibria of the proposed compounds.

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BRAGA, CAROLYNE B.; DUCATI, LUCAS C.; TORMENA, CLAUDIO F.; RITTNER, ROBERTO. Conformational Analysis and Intramolecular Interactions of L-Proline Methyl Ester and Its N-Acetylated Derivative through Spectroscopic and Theoretical Studies. Journal of Physical Chemistry A, v. 118, n. 9, p. 1748-1758, MAR 6 2014. (12/18567-4, 12/03933-5)

BRAGA, CAROLYNE B.; SILVA, WESLLEY G. D. P.; RITTNER, ROBERTO. Conformational preferences of N-acetyl-N-methylprolineamide in different media: a H-1 NMR and theoretical investigation. NEW JOURNAL OF CHEMISTRY, v. 43, n. 4, p. 1757-1763, JAN 28 2019. (12/18567-4, 16/24109-0, 16/12005-5)

SILVA, WESLLEY G. D. P.; BRAGA, CAROLYNE B.; RITTNER, ROBERTO. Conformational study of L-methionine and L-cysteine derivatives through quantum chemical calculations and 3J(HH) coupling constant analyses. Beilstein Journal of Organic Chemistry, v. 13, p. 925-937, MAY 17 2017. (12/18567-4, 14/25903-6, 16/12005-5)

BRAGA, CAROLYNE B.; DUCATI, LUCAS C.; RITTNER, ROBERTO. Experimental and theoretical evaluation on the conformational behavior of L-aspartic acid dimethyl ester and its N-acetylated derivative. RSC ADVANCES, v. 5, n. 23, p. 18013-18024, 2015. (12/18567-4, 12/03933-5)

BRAGA, CAROLYNE B.; RITTNER, ROBERTO. Combined Utilization of H-1 NMR, IR, and Theoretical Calculations To Elucidate the Conformational Preferences of Some L-Histidine Derivatives. Journal of Physical Chemistry A, v. 121, n. 3, p. 729-740, JAN 26 2017. (12/18567-4, 14/25903-6)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

BRAGA, Carolyne Brustolin. Conformational investigation of amino acid derivatives and corresponding intramolecular interactions through NMR and IR spectroscopies and theoretical calculations. 2016. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Química Campinas, SP.