A novel nanosized molten salt catalyst for the preparation of dihydropyrano[2,3-c]pyrazole derivatives

Heterocyclic structural kernels have found their prominent position among the therapeutic active molecules. These compounds play a critical role in molecular form of life like for example nucleotides, carbohydrates, hemes and amino acids. Specifically, nitrogen-rich heterocyclic molecules containing pyrazole moieties due to their privilege applications as biological and pharmacological active species, occupy a distinguished location in the domain of medicinal chemistry [1]. Among fused nitrogen-containing heterocyclic molecules, dihydropyrano[2,3- c]pyrazole derivatives which established significant precursors for the drug compounds, exhibit a broad scope of vital medicinal and pharmaceutical applications. They can be used as inhibitors of human Chk1 kinase, anti‐ inflammatory, anticancer, antimicrobial agents. Therefore, because of the high biological importance of these compounds, it is not surprising that several protocols have been reported for their preparation [2-3] (Scheme 1).