891190-58-2Relevant academic research and scientific papers
Microwave-assisted solution phase synthesis of dihydropyrimidine C5 amides and esters
Desai, Bimbisar,Dallinger, Doris,Kappe, C. Oliver
, p. 4651 - 4664 (2007/10/03)
Multifunctionalized dihydropyrimidine-5-carboxylic amides and esters are generated in a multistep sequence integrating a variety of enabling and high throughput technologies such as automated or parallel microwave synthesis, the use of polymer-supported reagents, fluorous synthesis and purification strategies, and a continuous flow hydrogenation system. The key dihydropyrimidine-5-carboxylic acid intermediates are obtained in two steps by Biginelli multicomponent condensation of benzyl or allyl β-ketoesters with aldehydes and urea/thioureas, followed by suitable benzyl or allyl deprotection strategies. Further functionalization of the acid cores with amines using polymer-supported coupling reagents or with alcohols utilizing Mitsunobu chemistry provides the desired amides or esters, respectively.
