Alternative Synthesis of Tadalafil: PDE5 Inhibitor

Abstract

Two-step alternative synthesis of tadalafil (1) is described. The synthesis features Pictet–Spengeler type reaction and DCC (N,N′-dicyclohexylcarbodiimide)/HOBt (N-hydroxybenzotriazole)–mediated double amidation employing sarcosine ethyl ester hydrochloride.

Keywords:

• Double amidation
• erection
• phosphodiesterase
• Pictet–Spengeler reaction

ACKNOWLEDGMENTS

The authors thank the management of Dr. Reddy's Laboratories Ltd. for supporting this work.

Notes

DRL-IPD Communication Number IPDO-IPM-00116.