Thiourea to bicyclic scaffolds: highly regio- and stereoselective routes to dithiazolopyrimidines
作者:Lal Dhar S. Yadav、Vijai K. Rai
DOI:10.1016/j.tet.2007.04.033
日期:2007.7
Microwave-activated solvent-free Michael addition of 3-imino-1,4,2-dithiazoles to 4-arylidene-5(4H)-oxazolones furnished isolable adducts regio- and diastereoselectively, which underwent ring transformation to yield the target dithiazolopyrimidines. Alternatively, the similar conjugate addition of methanesulfinylmethylisothioureas to 4-arylidene-5(4H)-oxazolones diastereoselectively afforded Michael
在3-芳基-1,4,2-二噻唑的微波活化的无溶剂迈克尔加成反应中向4-芳叉基5(4 H)-恶唑酮提供可分离的区域和非对映选择性加合物,将其进行环转化以生成目标二噻唑并嘧啶。备选地,将甲亚磺酰基甲基异硫脲类似的共轭加成至4-亚芳基-5(4H)-恶唑酮非对映选择性地,得到迈克尔加合物,其进行环转化,然后通过与亚硫酰氯的脱氧脱甲基化进行杂环化,以产生相同的二噻唑并嘧啶区域和非对映选择性的产物。