Table 1

Accurate mass determined on a quadrupole time-of-flight instrument for the parent and fragment ions of mercapturic acid derivatives of hydroxydiclofenac

5-OH-NAC-diclofenac (M1)
Ions	Calculated	Observed	Δ Da (×10³)	ppm
m/z473, C₁₉H₁₉N₂O₆SCI₂(MH⁺)	473.0341	473.0337	−0.4	−0.9
m/z 368, C₁₆H₁₂NO₃SCI₂	367.9915	367.9923	0.8	2.3
m/z 350, C₁₆H₁₀NO₂SCI₂	349.9809	349.9815	0.5	1.6
m/z 342, C₁₄H₁₀NO₃SCI₂	341.9758	341.9770	1.1	3.3
m/z 324, C₁₄H₈NO₂SCI₂	323.9653	323.9658	0.5	1.6
m/z 292, C₁₄H₈NO₂CI₂	291.9932	291.9935	0.3	1.1
m/z 162, C₅H₈NO₃S	162.0225	162.0221	−0.3	−2.2
m/z 130, C₅H₈NO₃	130.0504	130.0500	−0.4	−2.8

4′-OH-3′-NAC-diclofenac (M2)
Ions	Calculated	Observed	Δ Da (×10³)	ppm
m/z 473, C₁₉H₁₉N₂O₆SCI₂(MH⁺)	473.0341	473.0353	1.3	2.6
m/z 413, C₁₇H₁₅N₂O₄SCI₂	413.0130	413.0146	1.6	3.9
m/z 367, C₁₆H₁₃N₂O₂SCI₂	367.0075	367.0063	−1.2	3.3
m/z 350, C₁₆H₁₀NO₂SCI₂	349.9809	349.9825	1.6	4.6
m/z 324, C₁₄H₈NO₂SCI₂	323.9653	323.9666	1.3	3.9
m/z 294, C₁₄H₁₀NO₂CI₂	294.0089	294.0111	2.2	7.5
m/z 162, C₅H₈NO₃S	162.0225	162.0222	−0.2	−1.5
m/z 130, C₅H₈NO₃	130.0504	130.0503	−0.1	−0.7

Δ Da, the difference between observed and calculated values.