ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 54, Number 4
JKCSEZ 54(4)
August 20, 2010 

HPLC analysis of a commercial herb drink marketed as a functional food revealed to contain an unauthorized substance similar to sildenafil, the active ingredient of the prescription drug Viagra^? approved for the treatment of male erectile dysfunction. In order to identify the illegal additive, the herb drink was extracted with methylene chloride, and the extract was purified further using semipreparative HPLC. The chemical structure of the isolated substance was elucidated based on IR, LC/MS-ESI, and NMR spectroscopy, which showed the characteristics similar to sildenafil with minor modification. The only difference was the substitution of the methylpiperazine moiety of sildenafil to the hydroxyethylpiperazine group of the illegal additive.