In this contribution, we provide a comprehensive overview of acyclic twisted amides, covering the literature since 1993 (the year of the first recognized report on acyclic twisted amides) through June 2020. The review focuses on classes of acyclic twisted amides and their key structural properties, such as amide bond twist and nitrogen pyramidalization, which are primarily responsible for disrupting n_N to π*_C═O conjugation. Through discussing acyclic twisted amides in comparison with the classic bridged lactams and conformationally restricted cyclic fused amides, the reader is provided with an overview of amidic distortion that results in novel conformational features of acyclic amides that can be exploited in various fields of chemistry ranging from organic synthesis and polymers to biochemistry and structural chemistry and the current position of acyclic twisted amides in modern chemistry.

中文翻译：

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无环扭曲酰胺

在这篇文章中，我们提供了无环扭曲酰胺的全面概述，涵盖了自 1993 年（第一份公认的无环扭曲酰胺报告的年份）到 2020 年 6 月的文献。综述重点关注无环扭曲酰胺的类别及其关键结构特性，例如酰胺键扭曲和氮锥体化，它们主要负责将n _N破坏为 π* _C=O共轭。通过讨论无环扭曲酰胺与经典的桥连内酰胺和构象受限的环状稠合酰胺的比较，为读者提供了酰胺扭曲的概述，该扭曲导致了无环酰胺的新构象特征，可用于各种化学领域，从有机合成和聚合物到生物化学和结构化学以及无环扭曲酰胺在现代化学中的当前位置。