The synthesis of one H‐2 labeled and two H‐3 labeled leukotriene C4 synthase inhibitors

As part of a medicinal chemistry program aimed at developing a leukotriene C4 synthase inhibitor for the treatment of asthma, two tritium‐labeled and one stable isotope‐labeled compounds were required. The synthesis of the tritium‐labeled compounds used a standard bromination‐tritiodehalogentation approach. One of the tritium‐labeled compounds was observed to exchange its tritium label slowly with the solvent. The stable isotope‐labeled compound was prepared in seven steps (3% overall yield) from [ 2 H 6 ]acetone in a modification of the route used by medicinal chemistry.