Four-component, one-pot synthesis of spiropyrazolo pyrimidine derivatives by using recyclable nanocopper ferrite catalyst and antibacterial studies

A simple, efficient, ecofriendly, and cost-effective method has been developed for the synthesis of 16 spiropyrazolo pyrimidine derivatives (5a-5p) by a four-component, one-pot reaction of pyrimidine-2,4,6 (1H, 3H, 5H)-trione, 3-oxo-3-phenylpropanenitrile, hydrazine, and isatins (4a-4f) by using nanocopper ferrite catalyst (20 mol%) in water with excellent yields (73-91%). The isatin with electron-withdrawing groups gave products in high yields (5h and 5p). The present methodology offers an environmentally benign, cost-effective, high-yielding method with recyclable catalyst. The drug likeness or "drugability" of all the synthesized compounds were tested through rule of five (RO5) parameters. Compounds 5f, 5h, 5n, and 5p have shown one RO5 violation each. The compounds were screened for their antibacterial activity against human pathogenic bacteria wherein two of the synthesized compounds were found to possess significant antibacterial activity. Compounds showing RO5 violations had negligible antibacterial activity.