sildenafil molecular structure, 3d model molecule, phosphodiesterase type 5 inhibitors, structural chemical formula view from a

sildenafil phosphodiesterase type inhibitors erectile dysfunction pulmonary arterial hypertension molecule molecular structure chemical formula 3d model c22h30n6o4s atom chemistry science medicine healthcare and drug carbon material oxygen hydrogen medication erection shape disease medical research scientific treatment weekend atomic biochemistry compound pill nitrogen oxide