Avanafil-¹³C₅,¹⁵N,d₂ is ¹⁵N and deuterated labeled Avanafil (HY-18252). Avanafil (TA-1790) is a potent and selective phosphodiesterase-5 (PDE-5) inhibitor with IC₅₀ values of 5.2 nM, 630 nM, 5700 nM, 6200 nM, 12000 nM, 27000 nM, 51000 nM and 53000 nM for PDE-5, PDE-6, PDE-4, PDE-10, PDE-8, PDE-7, PDE-2 and PDE-1, respectively. Avanafil activates NO/cGMP/PKG signaling-pathway to decrease loss in BMD, bone atrophy, and oxidative stress. Avanafil inhibits cyclic guanosine monophosphate (cGMP) hydrolysis and thus increases cGMP levels. Avanafil can be used for the research of erectile dysfunction and osteoporosis^[1][2][3].