The novel synthesis of the protease inhibitor (S)-1-chloro-3-[(p-tolylsulfonyl)amino]-7-amino-2-[5,5,6,6-3H]heptanone ([3H]TLCK) labeled to high specific activity with tritium

Abstract

The protease inhibitor (S)‐1‐chloro‐3‐[(p‐tolylsulfonyl)amino]‐7‐amino‐2‐[5,5,6,6‐3H]heptanone ([3H]TLCK) was prepared in an overall 41% radiochemical yield with a specific activity of 1.6 Ci/mmol in a ‘one‐pot’ 3 step sequence beginning with (S)‐6‐[[(1,1‐dimethylethyl)oxy]carbonyl]‐2‐(p‐tolylsulfonyl)amino[4,4,5,5‐3H]hexanoic acid. The latter was prepared with a specific activity of 123 Ci/mmol in a 3 step sequence beginning with the stereospecific enzymatic hydrolysis of the commercially available racemic 2‐acetylamino‐6‐[[(1,1‐dimethylethyl)‐oxy]carbonyl]aminohexan‐4‐ynoic acid, followed by tosylation and then palladium catalyzed reduction of the triple bond under tritium. © 1997 John Wiley & Sons, Ltd.