The hybrid peptides consisting of α and β-amino acids show great promise as peptidomimetics that can be used as therapeutic agents. Therefore, the development of new unnatural amino acids and the methods of their incorporation into the peptide chain is an important task. Here, we described our investigation of the possibility of 5-amino-3-methyl-isoxazole-4-carboxylic acid (AMIA) application in the solid phase peptide synthesis. This new unnatural β-amino acid, presenting various biological activities, was successfully coupled to a resin-bound peptide using different reaction conditions, including classical and ultrasonic agitated solid-phase synthesis. All the synthesized compounds were characterized by tandem mass spectrometry. The obtained results present the possibility of the application of this β-amino acid in the synthesis of a new class of bioactive peptides.

中文翻译：

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5-氨基-3-甲基-异恶唑-4-羧酸作为一种新型非天然氨基酸在α/β-混合肽的固相合成中的应用

由α和β-氨基酸组成的杂合肽作为可用作治疗剂的肽模拟物显示出巨大的前景。因此，开发新的非天然氨基酸及其掺入肽链的方法是一项重要任务。在这里，我们描述了我们对 5-氨基-3-甲基-异恶唑-4-羧酸 (AMIA) 在固相肽合成中的应用可能性的调查。这种具有多种生物活性的新型非天然 β-氨基酸使用不同的反应条件（包括经典和超声搅拌固相合成）成功地与树脂结合的肽偶联。所有合成的化合物均通过串联质谱进行表征。