Amino Acids and Peptides. L. Development of a Novel N.PI.-Protecting Group for Histidine, N.PI.-2-Adamantyloxymethylhistidine, and Its Application to Peptide Synthesis.
作者:Yoshio OKADA、Jidong WANG、Takeshi YAMAMOTO、Toshio YOKOI、Yu MU
DOI:10.1248/cpb.45.452
日期:——
Nα-tert-Butyloxycarbonyl-Nπ-2-adamantyloxymethylhistidine, Boc-His(Nπ-2-Adom)-OH, was prepared by the reaction of Boc-His (Nτ-Boc)-OMe with 2-adamantyloxymethyl chloride (2-Adom-Cl), followed by saponification. The 2-Adom group was stable to trifluoroacetic acid (TFA), 1 N NaOH and 20% piperidine/DMF and easily removed by 1 M trifluoromethanesulfonic acid-thioanisole/TFA and HF. This new protecting group suppressed recemization during peptide synthesis and exhibited high solubility in organic solvents. It was applied to the synthesis of thyrotropin-releasing hormone (TRH) using both solution and solid-phase methods. The Nπ-2-Adom group can be used for peptide synthesis in combination with the tert-butyloxycarbonyl group as the Nd-protecting group in both solution and solid-phase methods.
Nα-tert-Butyloxycarbonyl-Nπ-2-adamantyloxymethylhistidine, Boc-His(Nπ-2-Adom)-OH, 是由 Boc-His (Nτ-Boc)-OMe 与 2-adamantyloxymethyl chloride (2-Adom-Cl) 反应,然后皂化制备的。2-Adom 基团对三氟乙酸 (TFA)、1 N NaOH 和 20% 的哌啶/DMF 很稳定,并且很容易被 1 M 三氟甲磺酸-硫代苯甲醚/TFA 和氢氟酸去除。这种新的保护基团可抑制多肽合成过程中的析出,并在有机溶剂中具有高溶解性。研究人员采用溶液法和固相法将其用于合成促甲状腺激素释放激素(TRH)。在溶液法和固相法中,Nπ-2-Adom 基团可与叔丁氧羰基作为 Nd 保护基团结合用于多肽合成。