The reaction of 2'-hydroxychalcone dibromides 1 or α-bromo-2'-hydroxychalcones 15 with sodium azide resulted in a mixture of α-azido-2'-hydroxychalcones 2, 3-aryl-5-(2-hydroxy-pheny)isoxazoles 3, flavones 4, aurones 5 and 4-aryl-5-(2-hydroxybenzoyl)-1,2,3-triazoles 6. The product ratio was strongly influenced by the character of the substituent at position C-4. Similar results were obtained with 2