A series of condensation products of 1-(9-butylcarbazol-3-yl)-5-oxopyrrolidine-3-carbohydrazide with 2-propanone, 2-butanone, 2,4-pentanedione, 2,5-hexanedione, ethyl 3-oxobutanoate, and aromatic aldehydes was obtained. Substituted oxadiazoles were synthesized from carbohydrazide or the corresponding hydrazone. Spectral properties of the synthesized compounds were examined.