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Updated: Aug 22, 2026

Technical Approach for Structural Analysis of an Unknown Compound in Huoxiang Zhengqi Oral Liquid based on Linear Ion Trap Mass Spectrometry
Published on: April 3, 2026
Structure determination of a sildenafil analogue contained in commercial herb drinks
Choonshik Shin1, Mooki Hong, Daibyung Kim
1Bio/Molecular Informatics Center, Konkuk University, Hwayang-Dong 1, Kwangjin-Ku, Seoul 143-701, Korea.
Abstract:
It was found from HPLC analysis that a commercial herb drink contains a putative sildenafil analog. In order to identify the sildenafil-like compound, separation and purification were carried out. The structure determination was performed based on routine 1D and 2D NMR experiments. Unlike sildenafil, the compound contains an ethylpiperazine instead of a methylpiperazine group. In addition, the piperazine and phenyl groups are connected through an acetyl group instead of the sulfonyl group of sildenafil.
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