ABSTRACT
Since a very long time the usefulness and great therapeutic value of pyrazole nucleus has been recognized and the wide range of activities of this nucleus evaluated. However antipyrine was the first synthetic organic compound having pyrazolin-5-one nucleus, to find use as an important drug. Phenylbutazone a prototype of pyrazolidinedione is very potent anti-inflammatory agent but its use is now banned in some countries. Later on many modifications of pyrazole nucleus were attempted and several compounds have been synthesized which serve as basis for treatment of different diseases, like-inflammation, pain, cancer, tuberculosis and disease caused by bacteria. COX-2 inhibitory activities of pyrazoles are well proved and many compounds containing pyrazole nucleus like Celecoxib, Sulphenazole, Sulphinpyrazole and Analgin are well established in the market. The discovery of natural 4-Hydroxy Pyrazole C-glycoside antibiotic pyrazofurin; 4-hydroxy-3beta-D-ribofuronasyl-IH-pyrazole-5-carboxamide; has provided a basis for more rational design and synthesis of new pyrazoles as potential antimicrobial, antiviral, anticancer agents