Inhibitory effect of novel pyrazole carboxamide derivatives on human carbonic anhydrase enzyme

Abstract

The synthesis, characterization and biological evaluation of novel pyrazole carboxamide derivatives (2–9) are presented. ¹H and ¹³C NMR have been used for the structure description, possible tautomeric structures determination and hydrogen bonding observation. FT-IR results have confirmed the synthesis of the pyrazole derivatives while thermal gravimetric analysis has confirmed thermal stability up to 300°C. The melting temperatures are strongly dependent on their crystal structure as confirmed by differential scanning calorimetry and X-ray diffraction measurements. Impacts of 2–9 as possible antiglaucoma agents were investigated on carbonic anhydrase I and II (CA-I and II) isozymes purified from human erythrocytes in vitro. Compounds 3 and 9 had the highest inhibitory effect while compounds 6 and 8 showed the lowest inhibition.

Keywords::

• Pyrazole-3-carboxamide
• antiglaucoma
• inhibition effect
• hydrogen bonding
• tautomeric structures