A green, efficient and recyclable Fe+3@K10 catalyst for the synthesis of bioactive pyrazolo[3,4-b]pyridin-6(7H)-ones under "on water" conditions

An efficient regioselective one-pot three-component synthesis of 4-aryl-3-methyl-4,5-dihydro-1H-pyrazolo[3,4-b]pyridin-6(7H)-ones and their bis-derivatives (Table 3 and Fig. 2) catalyzed by Fe+3-K10 montmorillonite (Fe+3@K10) under the Sharpless conditions (“On water” contdiions) is described. This rapid method produced the products in short reaction times (10–15 min) and excellent yields (87–95%). The antibacterial activity of the synthesized products was examined. Some products showed promising activities.