Medicinal Chemistry Research

, Volume 19, Issue 9, pp 1245–1258

Synthesis and pharmacological evaluation of newer thiazolo [3,2-a] pyrimidines for anti-inflammatory and antinociceptive activity

  • Ozair Alam
  • Suroor A. Khan
  • Nadeem Siddiqui
  • Waquar Ahsan
Original Research


A new series of thiazolo [3,2-a] pyrimidine derivatives was designed and synthesized using 4-fluoroaniline and ethylacetoacetate as starting material. Anti-inflammatory activity was assessed by the rat paw edema method and antinociceptive activity was evaluated by thermal stimulus technique. The compounds 5-(4-chlorophenyl)-2-(4-fluorobenzylidene)-7-methyl-3-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid (4-fluorophenyl)amide (3l) and 2-(4-chlorobenzylidene)-5-(4-fluorophenyl)-7-methyl-3-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid (4-fluorophenyl)amide (3q) were found to possess significant anti-inflammatory and antinociceptive activities. These compounds also showed lower ulcerogenic activity and higher ALD50 values. Compounds with an aryl ring substituted with a smaller electron withdrawing group at the fourth position displayed better activity than the other derivatives.


Thiazolopyrimidine Anti-inflammatory Antinociceptive Acute toxicity 


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Copyright information

© Birkhäuser Boston 2009

Authors and Affiliations

  • Ozair Alam
    • 1
  • Suroor A. Khan
    • 1
  • Nadeem Siddiqui
    • 1
  • Waquar Ahsan
    • 1
  1. 1.Department of Pharmaceutical Chemistry, Faculty of PharmacyHamdard UniversityNew DelhiIndia

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