The Diels–Alder reaction has long been established as an extremely useful procedure in the toolbox of natural product chemists. It tolerates a wide spectrum of building blocks of different complexity and degrees of derivatization, and enables the formation of six-membered rings with well-defined stereochemistry. In recent years, many total syntheses of natural products have been reported that rely, at some point, on the use of a [4+2]-cycloaddition step. Among classic approaches, several modifications of the Diels–Alder reaction, such as hetero-Diels–Alder reactions, dehydro-Diels–Alder reactions and domino-Diels–Alder reactions, have been employed to extend the scope of this process in the synthesis of natural products. Our short review covers applications of the Diels–Alder reaction in natural product syntheses between 2017 and 2020, as well as selected methodologies which are inspired by, or that can be used to access natural products.1 Introduction2 Syntheses from 20173 Syntheses from 20184 Syntheses from 20195 Syntheses from 20206 Conclusion

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Diels-Alder 反应在天然产物合成中的最新应用（2017-2020）

Diels-Alder 反应早已被确立为天然产物化学家工具箱中极其有用的过程。它可以容忍各种不同复杂性和衍生化程度的构建块，并能够形成具有明确立体化学的六元环。近年来，已经报道了许多天然产物的全合成，它们在某些时候依赖于 [4+2]-环加成步骤的使用。在经典方法中，Diels-Alder 反应的几种改进，如杂-Diels-Alder 反应、脱氢-Diels-Alder 反应和多米诺-Diels-Alder 反应，已被用于扩展该过程在合成天然产品。我们的简短回顾涵盖了 2017 年至 2020 年期间 Diels-Alder 反应在天然产物合成中的应用，