The drug sildenafil, sold under the trade name Viagra, is a potent inhibitor of phos- phodiesterase V (PDE V), an enzyme found in high levels in the corpus cavernosum of the penis. Inhibitors of this enzyme enhance vascular smooth muscle relaxation and are used for treatment of male impotence. Following is an outline for a synthesis of sildenafil. H Me Me EtO N„H4 EtO (1) EtO НО (2) (3) (4) Pr Pr Pr Me Me Me Но H,N H,N (6) EtO (7) O,N H,N Pr Pr Pr Me Me Me H, Н. Н. EtO EtO EtO Pr Pr Pr 0=$=0 0=$=0 Sildenafil (Viagra) ČH3

The drug sildenafil, sold under the trade name Viagra, is a potent inhibitor of phos- phodiesterase V (PDE V), an enzyme found in high levels in the corpus cavernosum of the penis. Inhibitors of this enzyme enhance vascular smooth muscle relaxation and are used for treatment of male impotence. Following is an outline for a synthesis of sildenafil. H Me Me EtO N„H4 EtO (1) EtO НО (2) (3) (4) Pr Pr Pr Me Me Me Но H,N H,N (6) EtO (7) O,N H,N Pr Pr Pr Me Me Me H, Н. Н. EtO EtO EtO Pr Pr Pr 0=$=0 0=$=0 Sildenafil (Viagra) ČH3

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter19: Enolate Anions And Enamines

Section: Chapter Questions

Problem 19.63P

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