title: Tadalafil.
abstract: Tadalafil is PDE5 inhibitor that has recently been approved for the treatment of ED. The mechanism of action of tadalafil is similar to sildenafil and vardenafil through the inhibition of PDE. In both chemical structure and PDE subtype selectivity profile, tadalafil differs markedly from sildenafil and vardenafil. Compared with sildenafil and vardenafil, tadalafil exhibits a prolonged plasma residence and window of therapeutic response. The physical properties, spectroscopic data and chromatographic methods of determination of tadalafil are documented.
authors.affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Alaa A-M
authors.initials: AA
authors.lastname: Abdel-Aziz
authors.forename: Yousif A
authors.initials: YA
authors.lastname: Asiri
authors.forename: Adel S
authors.initials: AS
authors.lastname: El-Azab
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Al-Omar
authors.forename: Takehisa
authors.initials: T
authors.lastname: Kunieda