The biological formation of nitrogen–nitrogen (N–N) bonds represents intriguing reactions that have attracted much attention in the past decade. This interest has led to an increasing number of N–N bond-containing natural products (NPs) and related enzymes that catalyze their formation (referred to in this review as NNzymes) being elucidated and studied in greater detail. While more detailed information on the biosynthesis of N–N bond-containing NPs, which has only become available in recent years, provides an unprecedented source of biosynthetic enzymes, their potential for biocatalytic applications has been minimally explored. With this review, we aim not only to provide a comprehensive overview of both characterized NNzymes and hypothetical biocatalysts with putative N–N bond forming activity, but also to highlight the potential of NNzymes from a biocatalytic perspective. We also present and compare conventional synthetic approaches to linear and cyclic hydrazines, hydrazides, diazo- and nitroso-groups, triazenes, and triazoles to allow comparison with enzymatic routes via NNzymes to these N–N bond-containing functional groups. Moreover, the biosynthetic pathways as well as the diversity and reaction mechanisms of NNzymes are presented according to the direct functional groups currently accessible to these enzymes.

中文翻译：

---

氮-氮键酶促形成的最新进展和挑战


氮-氮 （N-N） 键的生物形成代表了在过去十年中引起广泛关注的有趣反应。这种兴趣导致越来越多的含 N-N 键的天然产物 （NPs） 和催化其形成的相关酶（在本综述中称为 NNzymes）被阐明和更详细地研究。虽然最近几年才有关于含 N-N 键的 NP 生物合成的更详细信息提供了前所未有的生物合成酶来源，但它们在生物催化应用中的潜力却很少被探索。通过这篇综述，我们不仅旨在全面概述具有假定 N-N 键形成活性的表征 NNzymes 和假设的生物催化剂，而且还从生物催化的角度强调 NNzymes 的潜力。我们还提出并比较了线性和环状肼、酰肼、重氮和亚硝基、三氮和三唑的常规合成方法，以便与通过 NNzymes 与这些含有 N-N 键的官能团的酶途径进行比较。此外，根据这些酶当前可获得的直接官能团，介绍了 NNzymes 的生物合成途径以及多样性和反应机制。