Combined theoretical and experimental study on the molecular structure, FT-IR, and NMR spectra of cyadox and 1,4-bisdesoxycyadox

1,4-Bisdesoxycyadox, a deoxidized metabolite of cyadox, was synthesised and characterized. Structural and conformational analyses were performed using theoretical calculations employing density functional theory (DFT). The molecular geometry was optimized using B3LYP method with 6-311+G(d,p) basis set and then it was compared with X-ray diffraction data of similar molecular compounds. From the optimized geometry of the molecule, vibrational frequencies of the title compounds were calculated via B3LYP/6-311+G(d,p) approach. The 1H and 13C NMR chemical shift were calculated by gauge-including atomic orbital method with B3LYP/6-311++G(2df,2pd) approach. Comparison of the experimental and calculated 1H and 13C chemical shifts resulted in the reliable assignment of cyadox and 1,4-bisdesoxycyadox. The first, second, total, and mean NO bond dissociation enthalpies were also obtained theoretically.

► 1,4-Bisdesoxycyadox (1,4-BDC) were synthesised as one of cyadox’s main metabolite.
► Theoretically optimized structure agree very well with the experimental findings of BDOC.
► BDOC was characterized by IR, 1H, 13C NMR spectra.
► Bond dissociation enthalpies of NO in BDOC were estimated theoretically.