Synthesis of 2‐amino‐1,5‐dihydro‐1‐(methyl‐¹³C)‐4H‐imidazol‐4‐one‐5‐¹³C (creatinine‐¹³C₂)

Abstract

Abstract 2‐Amino‐1,5‐dihydro‐1‐(methyl‐ 13 c)‐4h‐imidazol‐4‐one‐5‐ 13 c (creatinine‐ 13 C 2 ) ( 8 ) is synthesized as follows. Glycine‐2‐ 13 c ( 1 ) is tosylated; the product ( 2 ) is treated with iodomethane‐ 13 C; and the resultant doubly‐labeled product ( 3 ) is detosylated to yield sarcosine‐ 13 C 2 ( 4 ). Creatine‐ 13 C 2 ( 7 ) is obtained by treating 4 with 2‐methylisothiourea monohydriodide ( 5 ) or cyanamide ( 6 ). Dehydration of 7 under vacuum sublimation conditions gives 8 .