Isolation and identification of two novel PDE-5 inhibitors illegally added to pressed candies

Two novel phosphodiesterase 5 (PDE-5) inhibitors were detected in pressed candy using high-performance liquid chromatography (HPLC)-diode array detection. Following extraction with acetonitrile and sonication, the compounds were isolated and purified via semi-preparative liquid chromatography. Structural characterisation was achieved through high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy. The results indicate that both compounds possess identical UV absorption spectra. The molecular formulas of compounds 1 and 2 are C23H32N4O4 and C22H30N4O4, respectively, each featuring a pyrimidinone benzene structure with a single methylene group (-CH2) variation. As studies on these illicit compounds in functional foods have not been conducted, regulatory agencies must take note and incorporate them for the assessment of illicit additives in functional and healthcare foods.