Preparation of 2-(Propylamino)Ethanethiol 2- Chlorotrityl (PAET) Resin for the Synthesis of Peptide Thioesters
نویسندگان
چکیده
The preparation of peptide thioesters using Fmoc chemistry requires their synthesis as amides flowed by an N -> S-acyl shift reaction. Recently, bis(2-sulfanylethyl)amino-trityl-polystyrene (SEA) resin has been reported (1, 2), where the peptide is synthesized as a secondary amide, and the N -> S-acyl shift occurs by reaction of one of the two 2-sulfanylethyl groups. The PAET resin described herein is easily synthesized and results in di-substituted amide peptide that promotes the N -> S-acyl shift reaction when the single 2-sulfanylethyl isomerizes to the correct position. The rate of N -> S shift is superior to that of the cystamine adduct. A peptide-peat adduct supported a native chemical ligation (NCL) reaction in the presence of MesNa. The presence of a secondary amide with a single 2-sulfanylethyl is sufficient for the efficient production of peptide thioesters.
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