Proton NMR spectra of toborinone and its metabolites
| H | Chemical Shift (ppm) | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| DMSO-d6Toborinone | DMSO-d6M-1 | DMSO-d6M-2 | DMSO-d6M-3 | DMSO-d6M-4 | DMSO-d6M-5 | DMSO-d6M-6 | DMSO-d6M-71-a | DMSO-d6M-14-11-b | DMSO-d6M-14-21-b | D2O Toborinone | D2O M-9 | D2O M-10 | D2O M-11 | D2O MD-12 | D2O M-13 | |
| 2(1H)-Quinolinone nucleus | ||||||||||||||||
| 1-NH | 11.61 | 11.63 | 11.60 | 11.62 | 10.85 | 11.63 | 11.62 | 11.61 | 11.60 | 11.62 | ||||||
| 3 | 6.47 | 6.48 | 6.47 | 6.48 | 6.51 | 6.48 | 6.48 | 6.47 | 6.44 | 6.46 | 6.42 | 6.64 | — | 4.32 | — | 4.24 |
| 4 | 7.82 | 7.83 | 7.83 | 7.84 | 7.82 | 7.83 | 7.84 | 7.82 | 7.92 | 7.86 | 7.63 | 7.96 | 7.67 | 4.32 | 7.14 | 4.20 |
| 5 | 7.20 | 7.20, 7.21 | 7.21 | 7.21 | 7.04, 7.08 | 7.19 | 7.22 | 7.20 | 7.46 | 7.26 | 6.81 | 7.22 | 6.88 | 7.13 | 6.93 | 6.94, 6.95 |
| 7 | 7.13 | 7.13 | 7.14 | 7.15 | 6.87 | 7.15 | 7.16 | 7.13 | 7.17 | 7.12 | 6.98 | 7.27 | 7.03 | 6.91 | 6.96 | 6.815, 6.821 |
| 8 | 7.22 | 7.23 | 7.23 | 7.23 | — | 7.24 | 7.24 | 7.22 | 7.21 | 7.21 | 7.02 | 7.31 | 7.12 | 6.96 | 7.22 | 6.87 |
| Side chain | ||||||||||||||||
| 1′ | 3.90 | 3.92–3.96 | 3.91–4.01 | 3.87 | 3.90 | 3.82–3.91 | 3.86–4.04 | 3.86–3.91 | 4.05 | 3.99 | 3.98 | 4.28 | 4.02 | 4.09 | 4.06 | 4.00–4.02 |
| 3.99 | 4.01 | 3.98 | 3.98 | 4.35 | 4.10 | 3.99 | 4.33 | 4.05 | 4.12 | 4.09 | ||||||
| 2′ | 3.90 | 4.07 | 3.91–4.01 | 3.79 | 3.90 | 3.82–3.91 | 3.86–4.04 | 3.86–3.91 | 3.94 | 4.03 | 4.25 | 4.43 | 4.26 | 4.29 | 4.23 | 4.19–4.22 |
| 3′ | 2.56 | 2.77 | 2.66 | 3.45 | 2.62 | 3.11 | 2.77 | 2.56 | 2.67 | 2.59 | 3.17 | — | 3.15 | 3.19 | 3.16 | 3.13–3.15 |
| 2.64 | 2.90 | 2.74 | 3.27 | 2.90 | 2.64 | 2.76 | 2.69 | 3.23 | 3.22 | 3.25 | 3.22 | 3.17–3.22 | ||||
| —NH7.95 | ||||||||||||||||
| 2′-OH4.96 | 2′—OH 5.24 | |||||||||||||||
| 3′-OH4.67 | CO—CH 3 | |||||||||||||||
| 1.82 | ||||||||||||||||
| 3,4-Dimethoxybenzylamino portion | ||||||||||||||||
| 2" | 6.93 | 7.06, 7.07 | 6.97 | 6.95 | 7.57 | 6.88 | 6.92 | 7.04 | 6.949 | 6.99 | 7.12 | 7.01 | 7.04 | |||
| 5" | 6.85 | 7.05 | 7.39 | 6.86 | 6.94 | 6.68 | 6.82 | 6.81 | 6.86 | 6.92 | 7.05 | 6.94 | 6.966, 6.971 | |||
| 6" | 6.81 | 6.92 | 6.81 | 6.81 | 7.04 | 6.68 | 6.79 | 6.81 | 6.953 | 7.01 | 7.08 | 7.00 | 7.00 | |||
| 7" | 3.63, 3.66 | 3.89 | 3.74 | 3.64 | 3.86–4.04 | 3.60 | 3.62 | 3.57, 3.69 | 4.17, 4.19 | 4.156, 4.162 | 4.21, 4.22 | 4.19, 4.21 | 4.17–4.18 | |||
| 8" | 3.71 | 3.74 | 3.71 | 8"9" | — | 3.72 | 8"9" | 8"9" | 3.70 | 3.74 | 3.85 | 3.74 | 8"9" | |||
| 9" | 3.71 | — | — | 3.71, 3.72 | 3.73 | — | 3.70–3.71 | 3.700–3.704 | 3.70 | 3.75 | 3.87 | 3.77 | 3.75, 3.78 | |||
| Adduct | ||||||||||||||||
| G11-c4.98 | G11-c 4.76 | G11-c4.25 | G11-c4.30 | Cys-α | 3.89 | 3.73 | 4.08 | 4.13–4.19 | ||||||||
| G21-c3.24–3.27 | G21-c , 1-d | G21-c2.95 | G21-c3.00 | Cys-β | 3.29, 3.44 | 3.05, 3.09 | 3.16, 3.36 | 3.05–3.13 | ||||||||
| 2.79 | ||||||||||||||||
| G31-c3.24–3.27 | G31-c , 1-d | G31-c3.12 | G31-c3.14 | Gly-α 3.60, 3.64 | ||||||||||||
| G41-c3.24–3.27 | G41-c , 1-d | G41-c3.05 | G41-c3.05 | γ-Glu-α 3.62–3.64 | ||||||||||||
| G51-c3.34 | G51-c , 1-d | G51-c3.17 | G51-c3.19 | γ-Glu-β 2.01 | ||||||||||||
| γ-Glu-γ 2.37 | ||||||||||||||||
Samples were dissolved in deuterated dimethylsulfoxide (DMSO-d6) or deuterium oxide (D2O) and analyzed on a 400 MHz or 500 MHz spectrometer.
Cys, cysteine or cysteinyl unit of glutathione; Gly, glycinyl unit of glutathione; γ-Glu, γ-glutamyl unit of glutathione.
↵1-a M-7 was prepared by enzymatic hydrolysis of M-1.
↵1-b M-14-1 and M-14-2 were assigned as the respective glucuronides of R-(+)- andS-(−)-isomers of toborinone.
↵1-c G1–5 correspond to the positions of protons for the glucuronic acid portion as shown in fig. 3.
↵1-d Values denote interference with H2O protons.