Imidazo thiadiazoles synthesis

In a more recent example of a type B synthesis, the imidazolium-O-sulfate salt 81 reacts with CS2 to afford the imidazo[2,l-f][l,2,4]thiadiazole 82 (Equation 22) <2003JOC4791>. 

Gadad AK, Palkar MB, Anand K, Noolvi MN, Boreddy TS, Wagwade J (2008) Synthesis and biological evaluation of 2-trifluoromethyl/sulfonamido-5,6-diaryl substituted imidazo[2,l-b]-1,3,4-thiadiazoles a novel class of cyclooxygenase-2 inhibitors. Bioorg Med Chem 16 276-283... 

A simple and efficient method has been developed for the synthesis of 2,6-di-substituted-imidazo[2,l-b][l,3,4] thiadiazoles under microwave activation using 2-amino-5-substituted-l,3,4-thiadiazoles and appropriate bromoketones as starting materials. These reactions had the benefits like convenient operation, short reaction time, and good yields (Dhepe et al., 2012). 

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