The quinazoline scaffold is found in the chemical structure of many marketed drugs used in CNS disorders as antidepressants, anxiolytics, or hypnotics. Also, the carbamate ester derivatives have different certain therapeutic actions, such as hypnotic or parasympathomimetic ones. We have obtained new 4(3H)-quinazolinones by bringing together in the same structure the quinazoline nucleus and carbamate ester group. The compounds named Q1–Q5 were characterized by measuring the melting points, by determining the infrared and NMR spectra, and by elemental analysis. The pharmacological tests evidenced that the compounds have a very low acute toxicity, lethal doses being >2000 mg/kg bw. The compounds had different actions observed in forced swimming test (FST), tail suspension test (TST), or elevated plus maze (EPM), probably influenced by the presence of different radicals on the nucleus. Thus, Q1 with a nitro group in structure manifested the highest antidepressant effect, showing a reduction of immobilization time in FST and TST. On the other hand, Q3 and Q5, with two groups methoxy, respective ethoxy, had a slight anxiolytic effect, highlighted by an increase of the time spent in open arms and a decrease of the time spent in closed arms of EPM.
Part of the book: Quinazolinone and Quinazoline Derivatives