Table 1.
Comparison of the theoretical and measured m/z values for benthiavalicarb-isopropyl with different isotopic substitutions and resolution details.
| No. | Isotopic Species | Molecular Formula | Theoretical m/z [M+H]+ |
Resolution (FWHM 1) |
Measured m/z [M+H]+ |
Mass Accuracy 2 (ppm) |
|---|---|---|---|---|---|---|
| 1 | Monoisotopic species | 12C18H24FN3O332S | 382.15952 | 30,000 3 | 382.15981 | +0.76 |
| 42,000 3 | 382.15953 | +0.03 | ||||
| 2 | Carbon-13, singly substituted | 12C1713C1H24FN3O332S | 383.16287 | 30,000 | 383.16281 | –0.16 |
| 42,000 | 383.16329 | +1.10 | ||||
| 3 | Sulfur-34, singly substituted | 12C18H24FN3O334S | 384.15532 | 30,000 | 384.15898 4 | –18.87 |
| 42,000 | 384.15978 4 | –16.79 | ||||
| 4 | Carbon-13, doubly substituted | 12C1613C2H24FN3O332S | 384.16623 | 30,000 | 384.15898 4 | +9.53 |
| 42,000 | 384.15978 4 | +11.61 |
1 Full width at half maximum. 2 (Mass accuracy) = [(theoretical m/z) − (measured m/z)]/(theoretical m/z) × 106. 3 30,000 FWHM was measured using an LCMS-9030 and 42,000 FWHM using an X500R. 4 The peaks of isotopes No. 3 and 4 in the mass spectra were not separated in both resolutions.