N-(4-((6-bromopyrido[2,3-d]pyrimidin-4-yl)oxy)phenyl)morpholine-4-carboxamide is a derivative of pyrido[2,3-d]pyrimidine with anti-tumor, antibacterial, anti-inflammatory and anti-microbial effects. Using 2-aminonicotinic acid as the starting material, the title compound was prepared through esterification, bromo ring and chlorine reactions. 1H NMR, 13C NMR and HRMS confirmed the structure of the target compound. The precise structure of the compound N-(4-((6-bromopyrido[2,3-d]pyrimidin-4-yl)oxy)phenyl)morpholine-4-carboxamide was analyzed by single-crystal X-ray diffraction. The molecular structure was further calculated using density functional theory (DFT), compared with the X-ray diffraction value. The molecular electrostatic potential and frontier molecular orbitals of the title compound were further investigated using DFT.

In this present work, the title compound 1-(4-((6-bromopyrido[2,3-d]pyrimidin-4-yl)oxy) phenyl)-3-(2,4-difluorophenyl)urea (1) was synthesized and the structure was characterized by spectroscopy (FT-IR, 1H NMR, 13C NMR and MS). The single crystal of the title compound was confirmed by X-ray diffraction, and the optimized molecular crystal structure was determined based on DFT calculations using B3LYP/6-311G (2d, p) basis set, which was compared with the X-ray diffraction. The results of the conformation analysis indicated that the molecular structure optimized by DFT was consistent with the crystal structure determined by X-ray single crystal diffraction.