Synthesis of [2‐¹³C, 2‐¹⁴C]2‐aminoethanol, [1‐¹³C, 1‐¹⁴C]2‐chloroethylamine, N,N′‐bis([1‐¹³C, 1‐¹⁴C]2‐chloroethyl)‐N‐nitrosourea(BCNU) and N‐([1‐¹³C, 1‐¹⁴C]2‐chloroethyl)‐N‐nitrosourea(CNU)

Abstract

[2‐13C, 2‐14C]2‐Aminoethanol hydrochloride was prepared in good yield from Na*CN in a two step sequence by first converting the Na*CN to OHCH2*CN and then reducing the nitrile directly with a solution of borane‐tetrahydrofuran complex. The reaction procedure was simple and the pure product could be obtained readily. Using this specifically labelled precursor, the synthesis of [1‐13C, 1‐14C]2‐chloroethylamine hydrochloride, N‐([1‐13C, 1‐14C]2‐chloroethyl)‐N‐nitrosourea(CNU) and N,N′‐bis([1‐13C, 1‐14C]2‐chloroethyl)‐N‐nitrosourea(BCNU) in good yield without isotope scrambling was also reported.

A Critical Appraisal of the Evolution ofN-Nitrosoureas as Anticancer Drugs

“…A number of radioisotopes, such as 13 N, 15 N, 11 C, 13 C, 14 C, and 18 F have been incorporated into the N -nitrosourea structure by various synthetic methods. − Such compounds, 13 − 23 , are useful for the study of the chemical decomposition and the metabolism of nitrosoureas. The incorporation of these isotopes is shown in Schemes −13.…”

Synthesis of 18F-labelled 2-fluoroethyl-nitrosoureas

“…I ) A suspension of 2-fluoroethylamine hydrochloride (1) (400 mg, 4 mmol) in 15 mL dioxane was heated to 60°C, and phosgene gas was slowly bubbled through the suspension for 15 min. (A similiar procedure was reported for the synthesis of 2-chloroethylisocyanate (22).) The reaction mixture was stirred at 65OC for an additional 30 min.…”