A vardenafil analogue was found to be added illegally into a dietary supplement marketed for erectile dysfunction. Its structure was determined as 2-(2-ethoxyphenyl)-5-methyl-7-propyl-imidazo[5,1-f] [1,2,4]triazin-4(3H)-one. The sample was extracted with ethanol and isolated by column chromatography. The structure was identified with a series of 1-D and 2-D NMR techniques and LC/MS/MS. Having compared with structure of vardenafil, the data showed that the ethylpiperazinyl and sulfonyl of vardenafil were removed from the phenyl group. Since its structure was similar to that of vardenafil, side effects of vardenafil might associate with this analogue. This vardenafil analogue has been included in the inspection list of illegal adulterants in Taiwan.
Lai, K.-C.; Liu, Y.-C.; Tseng, M.-C.; Lin, Y.-L.; and Lin, J.-H.
"Isolation and identification of a vardenafil analogue in a dietary supplement,"
Journal of Food and Drug Analysis: Vol. 15
, Article 2.
Available at: https://doi.org/10.38212/2224-6614.2405