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Updated: Jun 30, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Modifying quinolone antibiotics yields new anxiolytics
Timothy B C Johnstone1, Derk J Hogenkamp, Leanne Coyne
1Department of Pharmacology, College of Medicine, University of California, Irvine, California 92697, USA.
Abstract:
Patients taking fluoroquinolone antibiotics such as norfloxacin exhibit a low incidence of convulsions and anxiety. These side effects probably result from antagonism of the neurotransmitter gamma-aminobutyric acid (GABA) at the brain GABA(A) receptor complex (GRC). Modification of norfloxacin yields molecules such as compound 4 that potentiate GABA action with alpha(2) subunit selectivity. Compound 4 is anxiolytic but does not cause sedation, and may represent a new class of ligands that have anxiolytic activity without sedative liability.
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