In vitro conjugation reactions of laromustine and VNP4090CE
Reproduced by permission from Nassar et al., Chem. Res. Toxicol., 2011 (Nassar et al., 2011).
| Compound No. | Proposed Structure | MW (amu) | RTa (min) | H-Db | N-rulec | RDBEd | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| 12C | 13C | Expected | Observed | Expected | Observed | Expected | Observed | |||
| M-1 |  | 227.3 | 229.3 | 17.5 | 3 | 3 | Odd | Odd | 1 | 1 |
| M-2 |  | 178.2 | 178.2 | 20.2 | 4 | 4 | No or Even | Even | 2 | 2 |
| M-3 |  | 413.5 | 415.5 | 27.6 | 6 | 6 | Odd | Odd | 4 | 4 |
| M-4 |  | 364.4 | 364.4 | 27.8 | 7 | 7 | No or Even | Even | 5 | 5 |
| M-5 |  | 441.5 | 443.5 | 33.4 | 7 | 7 | Odd | Odd | 5 | 5 |
| M-6 |  | 220.3 | 220.3 | 37.7 | 3 | 3 | No or Even | Even | 3 | 3 |
| M-7 |  | 269.3 | 271.3 | 43.0 | 2 | 2 | Odd | Odd | 2 | 2 |
| M-8 |  | 297.4 | 299.4 | 46.5 | 3 | 3 | Odd | Odd | 3 | 3 |
MW, molecular weight.
↵a Approximate retention time on LC-MS.
↵b The number of labile protons on the molecule; the protonating species in the H-D experiments is D and not H.
↵c If a compound has an odd mass it has an N atom in its structure, and contains an odd number of N atoms (1, 3, 5 etc.). If a compound has an even mass, it has either no N or an even number of N atoms in its structure (0, 2, 4 etc.); the nitrogen rule only applies to unprotonated, intact molecules.
↵d RDBE, sulfone oxygen atoms (i.e., those double-bonded to sulfur) do not count toward rings and double bonds, 13C=[chloroethyl-1,2].