synthesis of pyrazolopyranopyrimidines catalyzed by caffeine supported on boehmite nanoparticles and their evaluation for anti-bacterial activities

the reaction of 3-chloropropyl boehmite nanoparticles with caffeine and sulfuric acid afforded bnps-3-propyl-imidazolopyridinium hydrogen sulfate [bnps-caff]hso4 as a new bnps-supported ionic liquid (il) catalyst. [bnps-caff]hso4 proved to be an efficient heterogeneous catalyst for the synthesis of pyrazolopyranopyrimidines via a one-pot four-component reaction of hydrazine hydrate, ethyl acetoacetate, barbituric acid, and an aldehyde. the attractive features of this method are simple procedure, clean reaction, use of a reusable catalyst, easy workup, and performing a multi-component reaction (mcr) in water. a number of synthesized compounds were screened for their in vitro anti-bacterial activities against the gram-positive and gram-negative bacteria using a well-diffusion method.