Design and Microwave-assisted Synthesis of 1,3,4-Oxadiazole Derivatives for Analgesic and Anti-inflammatory Activity

1,3,4-Oxadizoles form a biologically important group of compounds having activities like analgesic, anti-inflammatory, bactericidal, antifungal, anticonvulsant, psychotropic, plant growth regulating and mono amino oxidase inhibition. This research has focused on the incorporation of the oxadiazole moiety into isoniazid because of their versatile biological action, to get 2-aryl-5-(4-pyridyl)-1,3,4-oxadiazole to explore the possibilities of some altered biological action. 1,3,4-Oxadiazole derivatives were synthesized by microwave-assisted synthesis and screened for their analgesic, anti-inflammatory activities. The synthesized compounds were characterized by Melting point, Thin layer chromatographyInfra red, Nuclear magnetic resonance spectroscopy, etc. Almost all the synthesized compounds possessed good activity as compared to the standard

The first example of the Fischer–Hepp type rearrangement in pyrimidines

A N-nitroso moiety can be used for the activation of chloropyrimidines toward a nucleophilic substitution reaction with amines. The subsequent treatment of the obtained products with aq H2SO4 can lead to either N-denitrosation to obtain 4,6-pyrimidinediamines or to a Fischer–Hepp type rearrangement to obtain 5-nitroso-4,6-pyrimidinediamines. It was found that the outcome of the reaction strongly depends on the structure of the pyrimidines. Activation of the pyrimidine ring by three groups with a positive mesomeric effect is crucial for the intramolecular nitroso group migration