Synthesis of [l-3H]morphine-6-beta-D-glucuronide

Tritiated morphine of high specific activity was protected at the 3-positio n by acetylation and subjected to glucuronidation by Koenigs-Knorr procedur e with methyl 2,3,4-tri-0-acetyl-1-bromo-1-deoxy-D-glucopyranuronate and si lver carbonate. Fully protected morphine-6-glucuronide was obtained in 42% yield and 95% radiochemical purity as determined by TLC-RAM. Alkali catalyz ed solvolysis in two steps furnished [1-H-3]morphine-6-beta-D-glucuronide i n 23% overall radiochemical yield and 99% radiochemical purity determined b y HPLC - liquid scintillation counting and TLC-RAM.