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Updated: Aug 15, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Substituted 6,7-dihydroimidazo[1,2-a]purin-9(4H)-ones
Journal of Medicinal Chemistry
|November 1, 1980
Summary
Researchers synthesized novel imidazo[1,2-a]purin-9(4H)-ones with improved antiallergic and bronchodilator effects. Compound 33 demonstrated superior potency and safety compared to theophylline, offering a promising therapeutic alternative.
Area of Science:
- Medicinal Chemistry
- Pharmacology
Background:
- Theophylline is a common bronchodilator but has limitations.
- Development of novel antiallergic and bronchodilator agents is needed.
Purpose of the Study:
- Synthesize and evaluate novel substituted 6,7-dihydroimidazo[1,2-a]purin-9(4H)-ones.
- Compare their antiallergic and bronchodilator activities with theophylline.
- Investigate structure-activity relationships and metabolic profiles.
Main Methods:
- Chemical synthesis of imidazo[1,2-a]purin-9(4H)-one analogues.
- Pharmacological evaluation of antiallergic and bronchodilator activities.
- Assessment of side effects, including motor activity and cardiovascular effects in rats.
Main Results:
- Several synthesized compounds showed enhanced antiallergic and bronchodilator activity.
- Compounds with a 4-(4-chlorobenzyl) group, specifically 33 and 40, exhibited optimal activity.
- Compound 33 was more potent than theophylline in reducing bronchospasms and had fewer side effects.
Conclusions:
- Novel imidazo[1,2-a]purin-9(4H)-ones represent a promising class of antiallergic and bronchodilator agents.
- Compound 33 offers a superior therapeutic profile compared to theophylline.
- Further development of these analogues is warranted for respiratory conditions.
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