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Updated: Oct 9, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Optimization of substituted N-3-benzylimidazoquinazolinone sulfonamides as potent and selective PDE5 inhibitors
1Departments of Discovery Chemistry and Metabolic and Cardiovascular Drug Discovery, Bristol-Myers Squibb Pharmaceutical Research Institute, P.O. Box 5400, Princeton, New Jersey 08543-5400, USA. david.rotella@bms.com
Abstract:
A previous report from these laboratories identified the N-3-benzylimidazoquinazolinone nucleus as a more selective PDE5 inhibitor template compared to the pyrazolopyrimidine of sildenafil. This paper describes in detail the structure-activity relationships of a set of sulfonamide analogues, several of which are both more potent and more selective PDE5 inhibitors in vitro than sildenafil. The synthesis, in vitro enzyme activity and selectivity, and in vitro functional and preclinical pharmacokinetic assessment of molecules in this series are described.
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