The synthesis of ¹³C₉-¹⁵N-labeled 3,5-diiodothyronine and thyroxine

Thyroid hormones undergo extensive metabolism to regulate hormone activity. A labeled thyroid hormone would be useful to track hormone metabolism through various pathways. While radiolabeled thyroid hormones have been synthesized and used for in vivo studies, a stable isotope labeled form of thyroid hormone is required for studying thyroid hormone metabolism by LC-MS/MS, an analytical technique that has certain advantages without the complications of radioactivity. Here we report the synthesis of ¹³C₉- ¹⁵N-T₂ and ¹³C₉-¹⁵N- T₄, two labeled thyroid hormone derivatives suitable for in vivo LC-MS/MS studies. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.