Synthesis of deuterium-labeled 5α-androstane-3α,17β-diol and its 17β-glucuronide

Using unlabeled androsterone as starting material, 5α-[16,16-2H2]androstan-3α-ol-17-one was synthesized by exchange using deuterated potassium methoxide. This labeled androsterone product was reduced by sodium borodeuteride, which gave predominantly trideuterated 5α-androstane-3α,17β-diol. The labeled androstanediol was conjugated with glucuronide by using the Koenig-Knorr reaction with methyl-I-bromo-I-deoxy-2,3,4-tri-O-acetyl-α-D-glucopyranosuronate. The dominant product was identified by thermospray high-performance liquid chromatography/mass spectrometry (MS) and electrospray MS as 5α-[16,16,17-2H3]androstane-3α,17β-diol,17β-glucuronide.