Ab initio calculations of 1H and 13C chemical shifts in anhydrodeoxythymidines

For relatively large (containing 16 non-hydrogen atoms each) organic molecules, anhydrodeoxythymidines, (1)H and (13)C NMR chemical shifts were predicted using CPHF-GIAO, DFT-GIAO, and SOS-DFPT-IGLO methods. Both ab initio optimized and experimentally derived geometries of studied compounds were investigated. In the majority of cases, good agreement of theoretical and experimental chemical shifts was obtained with an average rmsd for SOS-DFPT-IGLO, DFT-GIAO, and CPHF-GIAO calculations of 5.5, 5.2, and 6.6 ppm for (13)C and 0.233, 0.269, and 0.297 ppm for (1)H, respectively. The best overall performance was found with the SOS-DFPT-IGLO technique.