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Updated: Oct 28, 2026

Derivatization of Protein Crystals with I3C using Random Microseed Matrix Screening
Published on: January 16, 2021
Computational elucidation of divergent skeletal reconstruction driven by site-selective protonation in
Mingjing Tang1,2, Jianquan Jing1,2, Dongxu Ma1,2
1School of Astronautics, Northwestern Polytechnical University, Xi'an, Shaanxi 710065, China. xia_honglei@nwpu.edu.cn.
Abstract:
The mechanistic influence of protonation on the skeletal reconstruction of nitrogen-rich heterocycles currently remains largely unexplored. Herein, DFT calculations were performed to investigate the divergent conversion of o-aminotetrazole-based substrates into energetic azine N-oxides in a mixed-acid system. Protonation at the nitramine moiety facilitates water elimination and favors the formation of azide-substituted products, whereas protonation at the tetrazole ring promotes ring opening, HN3 extrusion, and the generation of carbonyl-substituted products. Aromaticity analysis revealed that diminished aromaticity of the protonated tetrazole unit correlates with an increased propensity for the formation of carbonyl-substituted products. These results explain how site-selective protonation dictates divergent reaction pathways and establish a preliminary structural-aromaticity correlation for synthesizing target products, offering vital theoretical insights for the design and synthesis of advanced azine N-oxide compounds.
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