Synthesis, Structural Characterization, Spectroscopic Properties, and Theoretical Investigation of Siderol Acetate

In the present study, siderol acetate (1) was synthesized from siderol isolated from endemic Sideritis species, then its chemical structure was determined by using various spectroscopic methods (FT-IR, 1H NMR, and 13C NMR). The geometrical parameters, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C NMR chemical shift values for siderol acetate in the ground state have been calculated using the Density Functional Theory (DFT) and Hartree–Fock (HF) methods with the 6-31G(d) basis set. The calculated vibrational frequencies and 1H and 13C NMR chemical shifts have been compared with experimental values. A combined study based on NMR data and quantum-mechanical calculations using DFT/GIAO indicate that 1 is the correct structure of the title molecule.