Unexpected regio- and stereoselective [4 + 3] cycloaddition reaction of azomethine ylides with benzylidene thiazolidinediones: synthesis of pharmacologically active spiroindoline oxazepine derivatives and theoretical study

An unexpected regio- and stereoselective [4 + 3] cycloaddition reaction of azomethine ylides with 5-benzylidenethiazolidine-2,4-diones has been successfully developed for the synthesis of the novel pharmacologically active 4′,5′-dihydro-3′H-spiro[indoline-3,2′-[1, 3] oxazepin]-2-one derivatives in basic condition. Easy purification, high yield, short experimental time and operational simplicity are specific advantages of this protocol....