Multicomponent synthesis of dihydropyrano[2,3-c]pyrazoles catalyzed by lipase from Aspergillus niger

- First four-component biocatalytic reaction in organic synthesis.
- First lipase catalyzed synthesis of biologically important dihydropyrano[2,3-c]pyrazole core.
- First catalytic application of lipase from Aspergillus niger in a multicomponent reaction.
- Catalytic efficiency, recyclability, and effect of solvents were thoroughly studied.
- Easy access of dihydropyrano[2,3-c]pyrazoles from less reactive aliphatic aldehydes and ketones.