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 H 2 O 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 H 2 O 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.

Aerial oxidative cyclization of methylenebisnaphthols to their corresponding spirans has been carried out using catalytic amounts of N-hydroxyimides and FeCl3·6H2O or Co(OAc)2·4H2OMn( OAc)2·4H2O. In this article we focus on the use of FeCl3·6H2O as a highly green and sustainable catalyst.

in Wiley Online Library (wileyonlinelibrary.com).Herein, a novel and convenient procedure is described for the preparation of 1,3-dibenzylimidazolidine-2,4,5-triones. This method is based on a multi-stage oxidation of hexabenzylhexaazaisowurtzitanes by hydrogen peroxide in acetic acid, leading to the title compounds in relatively good yields.

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. -The reaction works well in the case of 2-mono-, 3-mono-and di-substituted benzaldehydes (II) but fails with 4-substituted benzaldehydes (V) forming intermediate Knoevenagel adducta (VI) only instead. A conventional heating method gives lower yields in all cases. Compounds (IVb)-(IVh) are tested against 6 bacterial species (Bacillus cereus, Bacillus thuringiensis, Staphylococcus aureus, Escherichia coli, Serratia marcescens and Shigella boydii). All compounds display significant activities against B. cereus and B. thuringiensis. -(KHORAAMABADI-ZAD*, A.; AZADMANESH, M.; KARAMIAN, R.; ASADBEGY, M.; AKBARI, M.; RSC Adv. 4 (2014) 88, 47721-47725, http://dx.doi.org/10.1039/C4RA07096H ; Fac. Chem., Bu-Ali Sina Univ., Hamedan 65178, Iran; Eng.) -M. Tismer