A convenient and rapid microwave-assisted synthesis of spirooxindoles in aqueous medium and their antimicrobial activities

A simple, ecofriendly and one-pot three-component aqueous phase protocol is developed for the synthesis of functionalized spirooxindole derivatives by the reaction of isatin, β-nitrostyrene and benzyl amine/α-amino acids in water under microwave irradiation. The method allows the easy construction of a library of spirooxindoles in moderate to good yields with good diastereoselectivity starting from readily available precursors. In addition, all the synthesized compounds were screened for antimicrobial activity and the majority of compounds showed significant activity against Escherichia coli ATCC 10536, Candida tropicalis ATCC 750, Staphylococcus aureus ATCC25923 and Pseudomonas aeruginosa ATCC 15442. An efficient, regioselective and diastereoselective synthesis of diversely functionalized spirooxindoles under microwave irradiation in aqueous medium; most of the compounds show significant antimicrobial activities.