*3.8. DP4 Analysis*

Conformational searches were performed using MacroModel software (Version 9.9, Schrödinger LLC, New York, NY, USA) interfaced in Maestro (Version 9.9, Schrödinger LLC) with a mixed torsional/low-mode sampling method. Conformers within 10 kJ/mol found in the MMFF force field were regarded and the geometry of the conformers was optimized at the B3-LYP/6-31G++ level in the gas phase. Ground state geometry optimization of each conformer was carried out by density functional theory (DFT) modeling with TurbomoleX 4.3.2 software. The basis set for the calculation was def-SVP for all atoms, and the level of theory was B3-LYP at the functional level in the gas phase. The calculated chemical shift values were averaged by the Boltzmann populations and utilized for DP4 analysis.
