Isolation and Identification of a Vardenafil Analogue in a Functional Food Marketed for Penile Erectile Dysfunction
Kuo-Chih Lai1, Yi-Chu Liu1, Mu-Chang Tseng1, Yun-Lian Lin2 and Jer-Huei Lin1*
1. Bureau of Food and Drug Analysis, Department of Health, Executive Yuan, 161-2, Kuen Yang St., Nankang, Taipei 115, Taiwan, R.O.C.
2. National Research Institute of Chinese Medicine, 155-1, Sec. 2, Li Nung St., Peitou, Taipei 112, Taiwan, R.O.C.
(Received: May 5, 2006; Accepted: December 11, 2006)
ABSTRACT
A vardenafil analogue was found to be added illegally to a dietary supplement marketed for erectile dysfunction. The structure was determined as 2-[2-ethoxy-5-(piperidine-1-sulfonyl)-phenyl]-5-methyl-7-propyl-3H-imidazo[5,1-f]-[1,2,4]triazin-4-one and named as piperidenafil. The sample was extracted with ethanol and isolated by column chromatography. The structure was identified by a series of 1-D and 2-D NMR techniques, mass and LC/MS/MS. As compared with the structure of vardenafil, it is shown that the ethylpiperazine was switched to piperidine. Since its structure was similar to that of vardenafil, side effects of vardenafil might be associated with this analogue. Basic on the law, foods using any illegal additive such as synthetic chemical compounds shall not be sold, manufactured, imported, processed, used, prepared, stored or transported. Therefore, this vardenafil analogue has been included in the inspection list of illegal health-related substances in Taiwan.
Key words: vardenafil analogue, piperidenafil, isolated, identified, NMR, LC/MS/MS