A New Resin-Bound Universal Isonitrile for the Ugi 4CC Reaction: Preparation and Applications to the Synthesis of 2,5-Diketopiperazines and 1,4-Benzodiazepine-2,5-diones

The preparation and synthetic applications of a novel resin-bound isonitrile are described. The resin is an example of a novel convertible isonitrile that can be utilized in the Ugi multicomponent reaction. Base-activation of the resin-bound Ugi product results in cleavage via formation of a N-acyloxazolidone that is then trapped as a carboxylic acid ester. This resin and the methodology described are suitable for synthesizing diversity libraries of 2,5-diketopiperazines and 1,4-benzodiazepine-2,5-diones.