Isoxazole
Overview
 
Isoxazole is an azole
Azole
An azole is a class of five-membered nitrogen heterocyclic ring compounds containing at least one other non-carbon atom of either nitrogen, sulfur, or oxygen. The parent compounds are aromatic and have two double bonds; there are successively reduced analogs with fewer...

 with an oxygen atom next to the nitrogen. It is also the class of compounds containing this ring.
 
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