STRUCTURAL ANALYSIS OF KYNURENIC ACID AND DERIVATIVES BY NMR SPECTROSCOPY AND DFT CALCULATIONS

SHMIDT, MARÍA S.; MARTINI, MARÍA F.; OPPEZZO, GUIDO A.; MARTÍNEZ, JUAN M. LÁZARO; DI SALVO, FLORENCIA; FABIAN, LUCAS; MOGLIONI, ALBERTINA G.; BLANCO, MARÍA M.

JOURNAL OF MOLECULAR STRUCTURE

ELSEVIER SCIENCE BV

Año: 2024 vol. 1308 p. 138077 - 138091

0022-2860

The 4-quinolinone derivatives present a keto-enol tautomerism, which can be studied using different analytical techniques, including NMR. In this work, the spectroscopic study in solution of numerous derivatives with different substitution patterns in positions 1-4 of the quinolone rings, and their correlation with simulated spectra by density functional theory-gauge independent atomic orbitals method (DFT-GIAO) approximation is presented. Polyfunctionalized derivatives where the tautomeric equilibrium is blocked by N- or O-substitution allow us to observe the different behavior in chemical shifts by NMR. The study of some derivatives in the solid state by ss-NMR and X-ray Crystallography is also included.