Spectroscopic and Computational Study of the Ugi Cinnamic Adduct NGI25

The structure assignment and conformational analysis of cinnamic derivative N-benzyl-N-(2-(cyclohexylamino)-2-oxoethyl) cinnamamide (NGI25) was carried out through Nuclear Magnetic Resonance (NMR) spectroscopy, Molecular Dynamics (MD) and Quantum Mechanics (QM), i.e., semiempirical and Density Functional Theory (DFT) calculations. Specifically, homonuclear (2D-COSY, 2D-NOESY) and heteronuclear (2D-HSQC, 2D-HMBC) spectra were obtained. Through them, the resonant values of the hydrogens and their constituent carbons were identified. After structure identification, NGI25 was subjected to computational calculations to reveal its most favorable conformations. QM, MD were in agreement with the spatial correlations that were observed in 2D-NOESY spectra.