Novel applications of ethyl glyoxalate with the Ugi MCR

Abstract This letter describes novel high-yielding solution phase preparations of 1,4-benzodiazepine-2,5-dione, diketo-piperazine, ketopiperazine and dihydroquinoxalinone libraries via a UDC (Ugi/de-Boc/cyclization) strategy in combination with ethylglyoxalate. The methodology represents a ‘three step, one-pot procedure’, employing the Ugi multi-component reaction (MCR), followed by Boc deprotection and cyclization.