t-Butyloxycarbonyl: an ordinary but promising group for protecting peptides from deiodination.
In order to protect directly radioiodinated peptides from in vivo deiodination, a novel procedure was explored. Two peptides, Try-Gly-Gly-Gly-Gly-Gly-Cys-Asn-Gly-Arg-Cys (YG5) and t-Boc-Try-Gly-Gly-Gly-Gly-Gly-Cys-Asn-Gly-Arg-Cys (t-BOC-YG5) were synthesized and radiolabeled. A paired-label biodistribution study using [131I]t-BOC-YG5 and [125I]YG5 was undertaken in normal mice. Compared to [125I]YG5, [131I]t-BOC-YG5 was quite resistant to in vivo deiodination, resulting in rapid reduction of the radioactive background and negligible radioactivity accumulation in both thyroid and stomach. [131I]t-BOC-YG5 was also stable in human serum even after 24 h. In conclusion, the t-BOC group has the potential to protect peptide from deiodination.
Sun
Xin
X
Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Chu
Taiwei
T
Liu
Xinqi
X
Wang
Xiangyun
X
D000818:Animals; D005563:Formic Acid Esters / Q000737:chemistry*; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007457:Iodine Radioisotopes / Q000737:chemistry; D051379:Mice; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D013961:Thyroid Gland / Q000378:metabolism; D014018:Tissue Distribution
D005563:Formic Acid Esters; D007457:Iodine Radioisotopes; D009842:Oligopeptides; D019275:Radiopharmaceuticals; C511543:Tyr-Gly-Gly-Gly-Gly-Gly-Cys-Asn-Gly-Arg-Cys; C511544:t-Boc-Tyr-Gly-Gly-Gly-Gly-Gly-Cys-Asn-Gly-Arg-Cys; C000345:t-butyloxycarbonyl group