AN EFFICIENT METHOD FOR THE PREPARATION OF NEW ANALOGS OF LEUCETTAMINE B UNDER SOLVENT-FREE MICROWAVE IRRADIATION

A simple and efficient microwave-assisted protocol has been developed for the synthesis of new 2-amino-3,4-dihydro-4H-imidazol-4-one derivatives of leucettamine B. This solvent-free protocol involves sulphur/nitrogen displacement of 2-ethylthio-5-arylidene-imidazolone 5 with a variety of functionalized polar primary amines 6 and this general method afforded a small library of the desired pure products 7a-n in yields ranging from 33 to 92% in moderate reaction times (30-100 minutes).