Synthesis, Analgesic and Anti-inflammatory Activities of 3- Ethyl-2-substituted Amino-3H-quinazolin-4-ones

Rv Sheorey,A Thangathiruppathy,V Alagarsamy

doi:10.4314/tjpr.v12i4.21

Abstract

Purpose: To synthesize a series of novel 3-ethyl-2-substituted amino-quinazolin-4(3H)-ones and evaluate them for their analgesic and anti-inflammatory activities. Methods : The compounds, 3-ethyl-2-substituted amino-quinazolin-4(3H)-ones, were synthesized by reacting the amino group of 3-ethyl-2-hydrazino quinazolin-4(3H)-one with a variety of aldehydes and ketones. The synthesized compounds were characterized by Fourier transform infrared (FTIR), protonnuclear magnetic resonance spectroscopy (1H-NMR) and mass spectrometry. The purity of the compounds was determined by elemental analysis. Test for analgesic activity was performed by tail-flick technique using Wistar albino mice while anti-inflammatory activity was evaluated by carrageenaninduced paw oedema test in rats. Diclofenac sodium was used as positive control for both analgesic and anti-inflammatory activities. Results: The compound, 3-ethyl-2-(cyclohexylidene-hydrazino)-3H-quinazolin-4-one (AS1), emerged as the active analgesic (activity, 63.89 %) and anti-inflammatory (activity, 60.00 %) compound of the series, and compared well with the reference standard, diclofenac sodium, which exbited analgesic and anti-inflammatory activities of 62.04 and 65.11 %, respectively Conclusion : The compound (AS1) can serve as a lead molecule for further development to a clinically useful novel class of analgesic and anti-inflammatory agents. Keywords : Quinazoline, Analgesic, Anti-inflammatory, Synthesis

Highlights

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed for the treatment of acute and chronic inflammation, pain and fever
Most NSAIDs act via inhibition of cyclooxygenase, preventing prostaglandin biosynthesis
In the course of our going medicinal chemistry research program it was found that quinazolines and condensed quinazolines exhibit potent central nervous system (CNS) activities including analgesic, anti-inflammatory [5] and anticonvulsant behavior [6]

Summary

Introduction

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed for the treatment of acute and chronic inflammation, pain and fever. Most NSAIDs act via inhibition of cyclooxygenase, preventing prostaglandin biosynthesis. This mechanism of action is responsible for their main undesirable effects, gastrointestinal (GI) ulceration and, less frequently, nephrotoxicity. In the course of our going medicinal chemistry research program it was found that quinazolines and condensed quinazolines exhibit potent central nervous system (CNS) activities including analgesic, anti-inflammatory [5] and anticonvulsant behavior [6]. Quinazolin-4(3H)ones with 2,3-substitution are reported to possess significant analgesic, anti-inflammatory [7,8] and anticonvulsant activities [9].

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Conclusion