A computer-assisted structure elucidation scheme based upon the pattern of assembly of peaks in carbon-13/ proton NMR spectra

Abstract

Hashimoto, M.S., Tanaka, Y., Sasabuchi, H. and Hattori, C.F., 1989. A computer-assisted structure elucidation scheme based upon the pattern of assembly of peaks in carbon-13/proton NMR spectra. Chemometrics and Intelligent Laboratory Systems, 6: 143–155.The basic idea reported previously in the qualitative analysis of carbon-13 NMR spectra by a computer-assisted structure elucidation scheme was extended so that it is now applicable to proton NMR spectra.Peaks in proton NMR spectra were grouped into several multiple bands with an evaluation of whether the peaks are close to each other within ± σ ppm, or not. The multiple bands were further patterned to rectangles, of which the widths and lengths correspond to the patterned multiplicities and the intensities of the maximum peaks in the groups.The patterned spectra of unknown compounds were compared with those of reference spectra by evaluating the quantities proportional to the reciprocal of the difference of chemical shifts, that of the multiplicities and that of the intensities of the unknown and the reference spectra.The applicability of this method was examined for steroid compounds and it was shown that the method can be used for structure elucidation problems.