Synthesis and Pharmacological Investigation of 5-Substituted-3-methylsulfanyl-1H-pyrazole-4-carboxylic Acid Ethyl Esters as New Analgesic and Anti-inflammatory Agents

Abstract

Purpose:

To synthesize a new series of 5-substituted-3-methylsulfanyl-1H-pyrazole-4-carboxylic acid ethyl esters for their analgesic and anti-inflammatory activity.

Methods:

The title compound synthesized by reacting the amino group of 5-amino-3-methylsulfanyl-1H-pyrazole-4-carboxylic acid ethyl ester with acid anhydrides, acid chlorides and phenyl dithiocarbamates. The synthesized compounds were characterized by IR, ¹H-NMR and mass spectral data; the purity of the compounds was determined by elemental analysis. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic behaviour.

Results:

The compound 5-benzoylamino-3-methylsulfanyl-1-phenyl-1H-pyrazole-4-carboxylic acid ethyl ester (4c) emerged as the most active compound and exhibiting imperative analgesic and anti-inflammatory activities. Interestingly the test compounds showed only mild ulcerogenic potential when compared to indomethacin.

Conclusion:

The compound (4c) could serve as a lead molecule for further modification to obtain a clinically useful novel class of analgesic and anti-inflammatory agents.

Key words

pyrazole derivatives - analgesic - anti-inflammatory activity - ulcerogenic behaviour

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