Stereoselective synthesis of pyrrolidinyl glycines from nitrones: complementarity of nucleophilic addition and 1,3-dipolar cycloaddition
作者:Pedro Merino、Petra Pádár、Ignacio Delso、Muniappan Thirumalaikumar、Tomás Tejero、Lajos Kovács
DOI:10.1016/j.tetlet.2006.05.114
日期:2006.7
Epimeric pyrrolidinyl glycines, a sort of conformationally constrained α,β-diaminoacids, were stereoselectively prepared using complementary approaches based on nitrone chemistry. Nucleophilic additions to pyrrolidinyl nitrones and 1,3-dipolar cycloadditions of l-serine derived nitrones to form the corresponding hydroxylamines and isoxazolidines, respectively, provided key intermediates for the synthesis
异构体吡咯烷基甘氨酸是一种构象受限的α,β-二氨基酸,是利用基于硝酮化学的互补方法立体选择性地制备的。吡咯烷基亚硝基的亲核加成和1-丝氨酸衍生的亚硝基的1,3-偶极环加成分别形成相应的羟胺和异恶唑烷,为合成目标化合物提供了关键的中间体。亲核加成途径提供了顺式加合物,而1,3-偶极环加成方法则为制备相应的抗化合物提供了前体。