Biocatalytic Nitration of Aromatic and Heterocyclic Compounds: Current Status and Future Prospects

Nitro compounds are widely utilized as value added pharmaceuticals and explosives, the majority of which contain a nitro group on an aromatic or heterocyclic ring. Nitration of aromatic or heterocyclic rings typically relies on well‐established chemical methods, but the harsh conditions, unsatisfying selectivity, and low efficiency need to be solved for practical application. In contrast, biocatalytic nitration offers a promising alternative in the preparation of nitro compounds with complex aromatic and heterocyclic structures. The earliest nitrifying enzymes were found in the metabolic pathways of several natural products having aromatic or heterocyclic nitro groups. With evolved and engineered nitrifying enzymes, bio‐nitration can be achieved for the preparation of a broader range of unnatural nitro group containing compounds. This study provides a comprehensive summary of the representative nitro compounds having nitro groups on the aromatic and heterocyclic rings, the associated nitrifying enzymes, and the characteristics of representative nitrifying enzymes which present specific nitration mechanisms. This study also discusses challenges with current bio‐nitration techniques and proposes future opportunities for the application of bio‐nitration as a powerful tool in the synthesis of natural and unnatural nitro compounds.