Mass spectral coding technique for identification of drugs and related compounds in reference compendia

A modification of the spectral abbreviation technique originally described by Hites and Biemann is proposed for identifying compounds through a coding of mass spectral data. Data from 2 closely related compounds (trimethadione and paramethadione), acquired by using 3 instruments, are presented. The technique appears to overcome observed differences in low resolution spectra when the same compound is analyzed by electron impact on mass spectrometers differing in design, manufacturer, principle of ion separation,, and operator. A list of spectra coded by this technique could constitute a rapid manual system of reproducing mass spectral data, using the significant high mass ions of low abundance as well as the frequently more abundant lower mass ions. This system is compared with existing systems.