dehydration products, in agreement to previous studies. The protocol constitutes a valuable approach to the preparation of oxazolidinone-containing peptides, which are a recently emerging class of constrained peptidomimetics. As a representative example, an Oxd analogue of the endogenous opioid peptide endomorphin-1, characterized by an all-trans conformation, was readily prepared.
含有
丝氨酸或苏
氨酸残基的磺酰肽与双(琥珀
酰亚胺)
碳酸酯 (
DSC) 和
二异丙基乙胺 (DI
PEA) 环化,得到带有 2-oxo-1,3-oxazolidine-4-carboxylate (Oxd) 基团的肽,无论是在溶液中或在固相。序列中
丝氨酸或苏
氨酸残基的位置相对不重要。在相同条件下,相应的 Fmoc-或 Boc-肽产生脱
水产物,与之前的研究一致。该协议构成了一种制备含有
恶唑烷酮的肽的有价值的方法,这些肽是最近出现的一类受限
肽模拟物。作为一个代表性的例子,内源性阿片肽endomorphin-1的Oxd类似物很容易制备,其特征在于全反式构象。