Abstract Indole-3-carboxylic acid hydrazide 3 was prepared and was treated with aromatic aldehydes in ethanol to give the corresponding hydrazone derivatives 4–7 in good yields. The indole carbohydrazide was incorporated into the 3-indolyloxadiazoles 8–11 and 18, 3- indolyltriazoles 13–17 and 35, 3-indolylpyrazole derivatives 19–23 and carbamate derivatives 26–27. Furthermore, interaction of the carboazide 24 with hydrazine hydrate in ...