Structure elucidation of sildenafil analogues in herbal products

• Published in: Food additives and contaminants Vol. 21; no. 8; p. 737
• Main Authors: Blok-Tip, L, Zomer, B, Bakker, F, Hartog, K D, Hamzink, M, Ten Hove, J, Vredenbregt, M, De Kaste, D
• Format: Journal Article
• Language: English
• Published: England 01-08-2004
• Subjects: Carbolines - chemistry; Chromatography, Liquid - methods; Imidazoles - chemistry; Magnetic Resonance Spectroscopy - methods; Models, Chemical; Phosphodiesterase Inhibitors - chemistry; Piperazines - chemistry; Plant Preparations - chemistry; Purines; Sildenafil Citrate; Spectrometry, Mass, Electrospray Ionization - methods; Sulfones; Tadalafil; Triazines; Vardenafil Dihydrochloride; Vasodilator Agents - chemistry
• ISSN: 0265-203X
• DOI: 10.1080/02652030412331272467

The structure of unknown compounds present in herbal products was elucidated using liquid chromatography-electrospray ionization-mass spectrometry, direct-infusion electrospray ionization-mass spectrometry, and nuclear magnetic resonance. Compounds 1-3 were identified as sildenafil analogues, 1 bearing an N-ethylpiperazine moiety instead of an N-methylpiperazine, and an acetyl group instead of the sulfonyl group, named acetildenafil, 2 bearing an N-ethylpiperazine moiety instead of an N-methylpiperazine (homosildenafil), and 3 bearing an N-hydroxylethylpiperazine moiety instead of an N-methylpiperazine, named hydroxyhomosildenafil. When analysing products marketed for penile erectile dysfunction or marketed as aphrodisiacs, attention should be given to the possible presence of these components.