Triethanolamine as an inexpensive and efficient catalyst for the green synthesis of novel 1H-pyrazolo[1,2-a]pyridazine-5,8-diones under ultrasound irradiation in water and their antibacterial activity

Abstract

Triethanolamine was found to be an efficient catalyst for the synthesis of new 1H-pyrazolo[1,2-a]pyridazine-5,8-diones by a one-pot reaction of maleic hydrazide, with aromatic aldehydes and malononitrile in H₂O under ultrasonic irradiation. The advantages of this method are the use of an inexpensive and readily available catalyst, easy workup, improved yields, and the use of H₂O as a green solvent. To assess their antibacterial activity, all the synthesized compounds were dissolved in DMSO and subjected to biological evaluation using the disc diffusion method against 3 Gram positive and 3 Gram negative bacteria.