Table 1.
Characterization of forsythin metabolites in humans by UPLC/Q-TOF MS.
| Metabolite | Retention time (min) | Observed mass (m/z) | Mass error (ppm) | Elemental composition | Mass area (*103) | Metabolic pathway | ||
|---|---|---|---|---|---|---|---|---|
| Plasma | Urine | Feces | ||||||
| M0 | 7.54 | 533.2031 | 0.4 | C27H34O11 | 0.390 | 6.65 | – | Parent |
| M1a | 9.66 | 371.1484 | −4.3 | C21H24O6 | 0.344 | 0.611 | 6.00 | Hydrolysis |
| M2a | 6.83 | 451.1072 | 0.8 | C21H24O9S | 543 | 3390 | 543 | M1 sulfation |
| M3 | 5.89 | 467.1012 | −1.0 | C21H24O10S | – | 34.3 | 2.09 | M1 sulfation + oxidation |
| M4 | 7.28 | 519.1891 | 3.7 | C26H32O11 | – | 0.754 | – | Demethylation |
| M5-1 | 5.23 | 533.1664 | 0.1 | C26H30O12 | – | 26.2 | – | M4 oxidation + dehydrogenation |
| M5-2 | 5.77 | 533.1666 | 0.4 | C26H30O12 | – | 109 | – | M4 oxidation + dehydrogenation |
| M6 | 5.35 | 535.1819 | −0.4 | C26H32O12 | – | 50.7 | – | M4 oxidation |
| M7a | 5.91 | 547.1819 | −0.4 | C27H32O12 | 12.7 | 154 | – | M1 glucuronidation |
| M8 | 5.68 | 561.1619 | 1.1 | C27H30O13 | – | 2.04 | – | M7 oxidation + dehydrogenation |
| M9-1 | 5.29 | 563.1769 | −0.1 | C27H32O13 | – | 2.88 | – | M7 oxidation |
| M9-2 | 5.58 | 563.1756 | −2.3 | C27H32O13 | – | 5.17 | – | M7 oxidation |
| M10-1 | 4.19 | 613.1229 | −0.5 | C26H30O15S | 4.55 | – | – | M5 sulfation |
| M10-2 | 4.57 | 613.1236 | 0.6 | C26H30O15S | – | 18.4 | – | M5 sulfation |
aConfirmed using reference standards.