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Updated: Sep 13, 2025

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
The Final Steps in Pseudoiodinine Biosynthesis Feature Ring-Contractive N-N Bond Formation
Lingyi Zhu1, Xiaozheng Wang1, Qing Shi1
1State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Abstract:
Pseudoiodinine (PSD) is a N-N bond-containing natural product with profound antimicrobial and antifungal activities. In this work, we have completed the PSD biosynthetic pathway by explicating the final three steps, which involve an enigmatic N-N bond formation in a ring contraction process. As a starting material, 1,6-didesmethyltoxoflavin (1,6-DDMT) is sequentially methylated by PsdF and PsdA to give 5-methoxy-6-desmethyltoxoflavin (5-OCH3-6-DMT), which then undergoes oxidative decarboxylation for the ring-contractive N-N bond formation to generate the pyrazole ring catalyzed by PsdB, a novel vicinal oxygen chelate superfamily (VOC) protein. This is the first enzyme in the VOC family to catalyze such a reaction, providing new insight into N-N bond formation.
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