Gas Chromatography Electron Ionization Mass Spectral Analysis of Thio Analogues of Pyrimidine Bases: 5-Bromo-2,4-di-o-(m- and p-) chloro- (bromo-)benzylthiouracils and 6-methyluracils

Table 2

Elemental compositions and relative abundances of the ion peaks in the spectra of 7–12 according to the high-resolution data.

Ion	m/z	Elemental composition	% relative abundance (%RA)
			7	8	9	10	11	12
M ^+•	484/486/488	C19H15N2S2Cl2Br	20/41/24	25/48/24	21/33/16	—	—	—
a	572/574/576/578	C19H15N2S2Br3	—	—	—	17/54/53/17	13/44/49/20	14/35/44/18
b [a– ^•SH]	451/453/455	C19H14N2SCl2Br	12/9/4	10/14/7	7/10/4
	539/541/543/545	C19H14N2SBr3				3/5/9/3	4/19/15/6	2/10/12/4
c [a– ^•X]	449/451/453	C19H15N2S2ClBr	3/12/9	1/10/14	0.1/7/10
	493/495/497	C19H15N2S2Br2				6/15/11	12/23/8	3/5/3
d [a– ^•SH– ^•X]	416/418/420	C19H14N2SClBr	4/4/3	1/4/2	1/1/1
	460/462/464	C19H14N2SBr2				9/19/9	4/9/1	2/11/6
d′ [a–SH–HX]	415/417/419	C19H13N2SClBr	3/6/2	4/5/4	1/3/3
	459/461/463	C19H13N2SBr2				5/10/9	8/18/13	3/13/10
e	359/361/363 403/405/407	C12H9N2S2ClBr C12H9N2S2Br2	31/33/14	54/78/22	28/46/12	—	—	—
			—	—	—	48/81/44	52/100/57	35/72/44
f [e– ^•X]	324/326	C12H9N2S2Br	18/18	2/13	1/5	—	—	—
			—	—	—	70/70	12/10	12/11
g	125/127	C7H6Cl	100/31	100/34	100/33	—	—	—
	169/171	C7H6Br	—	—	—	89/91	73/70	98/95
h	90	C7H6	13	11	9	100	85	100
j	89	C7H5	57	66	41	81	76	94