Isolation and identification of a new acetildenafil analogue used to adulterate a dietary supplement: dimethylacetildenafil

摘要

A new sildenafil analogue was found to have been addedillegally to a dietary supplement marketed for the enhancement ofsexual function. The structure was determined as 5-(2-ethoxy-5-{[4-(3,5-dimethyl)piperazin-1-yl]-acetyl}phenyl)-1,6-dihydro-1-methyl-3-propyl-7H-pyrazolo [4,3-d]pyrimidin-7-one. Owing to the inclusion ofa dimethyl group in acetildenafil, the detected compound was calleddimethylacetildenafil. The sample was purified with columnchromatography. The IR, LC/MS (ESI), and completely assigned NMR dataof dimethylacetildenafil are reported for the first time. Thestructure was compared with that of acetildenafil and the resultsshowed that the ethyl substitution at the 4-position of the piperazinering had been replaced by a 3,5-dimethyl substitution. This newacetildenafil analogue was isolated and identified for the first time.