β-Cyclodextrin as a supramolecular catalyst for the synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives in water and their antimicrobial activities

An efficient and green method has been developed for the synthesis of 2H-indazolo[2,1-b]phthalazinetriones derivatives by employing 15 mol% beta-cyclodextrinvia a one-pot multicomponent reaction of aldehyde, dimedone, hydrazine hydrate with succinic anhydrideiphthalic anhydride in water at 80 degrees C for first time. The catalyst could be recovered and reused for four consecutive cycles without appreciable loss in catalytic activity and evaluated for in vitro antimicrobial activity against different Gram-positive and Gram-negative bacterial strains. The outcome of the screening study showed that compound 6d, 6f and 7n exhibited excellent activity against E. coil. Whereas, compound 6f and 6 h exhibited excellent activity against P. aeurginosa, and compound 6c, and 6e displayed again excellent activity against Staphylococcus aureus whereas compound 7o shows excellent activity against S. aureus and B. subtilis when compared with Ampicillin (standard control). The results indicated that maximum compounds are moderately effective against bacterial growth and their effectiveness is highest against standard drugs. (C) 2017 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.