Identification of a new type tadalafil analogue in a supplement product

A novel compound structurally similar to tadalafil was found in a dietary supplement by adulterants screening test and isolated by column chromatography. After analysis by accurate mass, nuclear magnetic resonance (NMR) and X-ray, the structure of this novel tadalafil analogue was determined as (5R, 16R)-5-(1,3-benzodioxol-5-yl)-2- (3-ethypentan-3-yl)-15,16-dihydro(1H-imidazo[1,5-a]pyrido)[3,4-b]indol-1,3-dion