The classical Prins cyclization has been one of the most intensively studied reactions during the last two decades, and it has found many applications in key steps of natural product syntheses, especially for products containing tetrahydropyran motifs and related structures in their core skeletons. The application of this reaction to the synthesis of spirocylic networks has made substantial progress recently. Spiro motifs are found in many natural products with promising biorelevance and are increasingly being incorporated in drug candidates. Further, various spirocyclic chiral ligands have shown promising efficiency in asymmetric synthesis. Here a compilation of recent spiroannulation reactions by Prins cyclization is presented, focusing on the scope and versatility of this method.

中文翻译：

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Prins螺环化的新进展

经典的 Prins 环化反应是过去二十年来研究最深入的反应之一，它在天然产物合成的关键步骤中得到了许多应用，尤其是在其核心骨架中含有四氢吡喃基序和相关结构的产物。该反应在螺环网络合成中的应用最近取得了实质性进展。螺旋基序存在于许多具有良好生物相关性的天然产物中，并且越来越多地被纳入候选药物中。此外，各种螺环手性配体在不对称合成中显示出良好的效率。这里介绍了最近通过 Prins 环化进行的螺环化反应的汇编，重点介绍了该方法的范围和多功能性。