MASS-SPECTROMETRY OF THIO ANALOGS OF PYRIMIDINE-BASES - CORRELATION OF THE INTENSITIES OF THE M(-(M--AND-P-) SUBSTITUTED BENZYLTHIOURACILS() AND SELECTED FRAGMENT IONS OF O)

The mass spectral fragmentations of sixteen new 2- and 4-o-(m- and p-) substituted benzylthiouracils and o-(m- and p-)substituted 2,4-dibenzy lthiouracils with NO2 and Cl substituents in the benzyl groups were in vestigated. Fragmentation pathways are proposed on the basis of accura te mass and metastable transitions measurements. The correlation betwe en the abundances of the M(+.) and the selected fragment ions of inves tigated compounds is discussed. The data obtained create the basis for distinguishing structural isomers.