Identification of a novel vardenafil analogue, 19-O-propyl hydroxy vardenafil, as a dietary supplement adulterant

Hui-Chun Lee; You-Lun Wu; Yu-Ting Lin; Li-Yao Tsai; Ya-Min Kao; Mei-Chih Lin; Su-Hsiang Tseng

doi:10.1016/j.jpba.2024.116563

Identification of a novel vardenafil analogue, 19-O-propyl hydroxy vardenafil, as a dietary supplement adulterant

J Pharm Biomed Anal. 2025 Jan 15:253:116563. doi: 10.1016/j.jpba.2024.116563. Epub 2024 Nov 4.

Authors

Hui-Chun Lee¹, You-Lun Wu², Yu-Ting Lin³, Li-Yao Tsai⁴, Ya-Min Kao⁵, Mei-Chih Lin⁶, Su-Hsiang Tseng⁷

Affiliations

¹ Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].
² Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].
³ National Health Insurance Administration, Ministry of Health and Welfare, No.15-1 Gongyuan Rd., Zhongzheng District, Taipei City 100-41, Taiwan, ROC. Electronic address: [email protected].
⁴ Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].
⁵ Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].
⁶ Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].
⁷ Division of Research and Analysis, Taiwan Food and Drug Administration, No.161-2 Kunyang St., Nangang District, Taipei City 115-61, Taiwan, ROC. Electronic address: [email protected].

PMID: 39541764
DOI: 10.1016/j.jpba.2024.116563

Abstract

A novel vardenafil analogue was discovered during adulterant screening of a dietary supplement. After extraction and purification, this analogue was identified using liquid chromatography-high resolution mass spectrometry (LC-HRMS) and nuclear magnetic resonance (NMR) analyses. The molecular formula determined using LC-HRMS was C₂₄H₃₄N₆O₅S. Fragmentation data suggested that this unknown compound may have two modifications to vardenafil. NMR analysis confirmed the presence of a hydroxyl group on the piperazine moiety and a propyl group attached to the phenoxy group. Consequently, this compound was named 19-O-propyl hydroxy vardenafil.

Keywords: 19-O-propyl hydroxy vardenafil; HRMS; NMR; PDE-5 inhibitor; Vardenafil analogue.

MeSH terms

Chromatography, Liquid / methods
Dietary Supplements* / analysis
Drug Contamination*
Magnetic Resonance Spectroscopy* / methods
Mass Spectrometry / methods
Triazines / analysis
Triazines / chemistry
Vardenafil Dihydrochloride* / analysis
Vardenafil Dihydrochloride* / chemistry

Substances

Vardenafil Dihydrochloride
Triazines