Solid-Supported Microwave-Accelerated Intramolecular Knoevenagel Hetero-Diels-Alder Reactions: A Protocol for the Synthesis of Indolo[2,1-a]pyrrolo[4′,3′:4,5]pyran Ring Systems - Manian, Rathna DurgaR S; Jayashankaran, Jayadevan; Raghunathan, Raghavachary (Synlett, 2007)