A successful approach to the construction of spiro-β-lactone-γ-lactam synthons 5 and ent-5 as a similar structural motif present in natural products such as oxazolomycins was developed. Two chirons, the protected 3-isothiocyanato-3-C-vinyl-α-d-xylofuranose and its antipode, were employed as the starting material. In order to obtain a lactone-pyrrolidine cyclic framework, a ring-closing metathesis, a highly diastereoselective reduction of a double bond and the formation of a β-lactone skeleton were involved as the key transformations. The final enantiomeric pharmacophores were screened for their capacity to alter the viability of cancer cells.

中文翻译：

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螺-β-内酯-γ-内酰胺支架的合成及体外细胞毒性评价

开发了成功的方法来构建螺-β-内酯-γ-内酰胺合成子5和ent - 5作为存在于天然产物（如恶唑霉素）中的类似结构基序。将两种被保护的3-异硫氰基-3- C-乙烯基-α - d-木呋喃糖及其对映体作为起始原料。为了获得内酯-吡咯烷环骨架，闭环易位，双键的高度非对映选择性还原和β的形成内酯骨架是关键的转变。筛选最终的对映体药效基团改变癌细胞存活力的能力。