title: Vardenafil dihydrochloride.
abstract: Vardenafil (VAR) is synthetic, highly selective, and potent inhibitor of phosphodiesterase-5 which competitively inhibits cyclic guanosine monophosphate (cGMP) hydrolysis and thus increases cGMP levels. It is clinically approved for treatment of erectile dysfunction in men, including diabetic and postprostatectomy patients. Several methods of VAR synthesis are included in this review. UV spectroscopy of VAR showed a λmax of approximately 270nm, and IR spectroscopy principal peaks were observed at 3420 (NH), 1724 (CO), 1600 (CC, and CN), 1491 (CHCH) cm(-1). Characteristic carbonyl (CO) carbon was observed in nuclear magnetic resonance spectroscopy at 162.44ppm. The molecular mass was observed at m/z=488.9 (molecular weight=488.2) and the fragmentation pattern was studied using ion trap mass spectrometry. In addition, different analytical methods for determination of vardenafil are also described in this profile. Pharmacokinetic properties of VAR have great impact on efficacy. VAR is rapidly absorbed and slowly metabolized, with an absolute bioavailability of 15%. It is extensively metabolized by CYP3A4 into several metabolites, the most pharmacologically active of which is N-desethyl VAR (M1). The elimination half-life of VAR and M1 is about 4-5h. VAR is primarily excreted as metabolites in the feces and to a small extent in urine. VAR is generally well tolerated, with a favorable safety profile and few transient side effects, including headache, flushing, dyspepsia, and rhinitis.
authors.affiliation: Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Abdelkader E
authors.initials: AE
authors.lastname: Ashour
authors.affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: A F M Motiur
authors.initials: AF
authors.lastname: Rahman
authors.affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Mohammed G
authors.initials: MG
authors.lastname: Kassem
mesh_terms: D000818:Animals; D002626:Chemistry, Pharmaceutical; D007172:Erectile Dysfunction / Q000188:drug therapy / Q000201:enzymology; D006801:Humans; D007093:Imidazoles / Q000032:analysis* / Q000737:chemistry* / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D015394:Molecular Structure; D058986:Phosphodiesterase 5 Inhibitors / Q000032:analysis* / Q000737:chemistry* / Q000493:pharmacokinetics / Q000627:therapeutic use; D010879:Piperazines / Q000032:analysis* / Q000737:chemistry* / Q000493:pharmacokinetics / Q000627:therapeutic use; D013450:Sulfones / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics / Q000627:therapeutic use; D014227:Triazines / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics / Q000627:therapeutic use; D000069058:Vardenafil Dihydrochloride
chemical_list: D007093:Imidazoles; D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D013450:Sulfones; D014227:Triazines; D000069058:Vardenafil Dihydrochloride
keywords: Analysis; Impotence; PDE-5 inhibitors; Pharmacokinetics; Safety; Synthesis; Vardenafil