中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
1-(2-氯乙基)-3-(2-氟乙基)脲 | 1-(2-chloroethyl)-3-(2-fluoroethyl) urea | 13907-93-2 | C5H10ClFN2O | 168.599 |
N-(2-氟乙基)-1-氮丙啶甲酰胺 | 1-(2-fluoroethyl)-3-ethylene urea | 93676-97-2 | C5H9FN2O | 132.138 |
18F-labelled 1,3-bis-(2-fluoroethyl) nitrosourea (18F-BFNU) (9) and 1-(2-chloroethyl)-3-(2-fluoroethyl) nitrosourea (18F-CFNU) (isomeric mixture, 11,12) were synthesized by nucleophilic attack of 18F-labelled tetra-n-butylammonium fluoride on the aziridine ring of 1,3-substituted ureas. Diethyleneurea (DEU) (5), 1-(2-fluoroethyl)-3-ethyleneurea (FEU) (7), and 1-(2-chloroethyl)-3-ethyleneurea (CEU) (14) were used as starting materials in the synthesis. Nitrosation of 18F-labelled 1,3-bis-(2-fluoroethyl) urea (18F-BFU) (6) produced 18F-BFNU with a radiochemical yield of 5–10%. Nitrosation of 18F-labelled 1-(2-chloroethyl)-3-(2-fluoroethyl) urea (18F-CFU) (15) gave 18F-CFNU as a mixture of two isomers. Geometrical isomers of CFNU were separated by hplc, and the radiochemical yield of the two isomers ranged from 8% to 15%, with a radiochemical purity exceeding 96%. Syntheses, which took about 60 min, yielded products with specific activity of 680 mCi/mmol when n-Bu4N+F− was used, or 300 mCi/mmol when HF was used to complete the opening of the aziridine ring.