Biorenewable and mercaptoacetylating building blocks in the Biginelli reaction: synthesis of thiosugar-annulated dihydropyrimidines
- 作者：Lal Dhar S. Yadav ; Chhama Awasthi ; Vijai K. Rai ; Ankita Rai
- 关键词：Biginelli reaction ; Stereoselective synthesis ; Dihydropyrimidines ; Microwaves ; 1 ; 3-Oxathiolan-5-one ; Solvent-free
- 刊名：Tetrahedron Letters
- 出版年：2007
- 期刊代码：109_00404039
- 类别：ch
- 出版时间：9 July 2007
- 卷：48
- 期：28
- 页码：4899-4902
- 文件大小：140 K
摘要
A novel version of the Biginelli reaction using an unprotected aldose as a biorenewable aldehyde component and 2-methyl-2-phenyl-1,3-oxathiolan-5-one as a mercaptoacetylating active methylene building block with urea/thiourea is reported. The reaction is nanoclay-catalysed, expeditious and effected under solvent-free microwave irradiation conditions in a one-pot procedure to yield diastereoselectively, thiosugar-annulated multifunctionalized dihydropyrimidines via intramolecular domino cyclocondensation reactions of an isolable intermediate.