Some Novel Mannich Bases of 5-(3,4-Dichlorophenyl)-1,3,4-oxadiazole-2(3H)-one and Their Anti-Inflammatory Activity.

Non-steroidal anti-inflammatory drugs (NSAIDs), which are widely used for the treatment of rheumatic arthritis, pain, and many different types of inflammatory disorders, cause serious gastrointestinal (GI) side effects. The free carboxylic acid group existing on their chemical structure is correlated with GI toxicity related with all routine NSAIDs. Replacing this functional group with the 1,3,4-oxadiazole bioisostere is a generally used strategy to obtain an anti-inflammatory agent devoid of GI side effects.