Synthesis of Oligomers of <i>trans</i>-(4<i>S</i>,5<i>R</i>)-4-Carboxybenzyl 5-Methyl Oxazolidin-2-one: An Approach to New Foldamers
作者:Simone Lucarini、Claudia Tomasini
DOI:10.1021/jo005583+
日期:2001.2.1
The synthesis of two oligomers containing three and four residues, respectively, of trans-(4S,5R)-4-carboxy 5-methyloxazolidin-2-ones is described. The monomer is obtained by starting from benzyl-N-Boc-(3R)-aminobutanoate, by cyclization into the corresponding trans-(2S,3R)-2-carboxybenzyl-3-methyl-N-Boc-aziridine and rearrangement of the product to trans-(4S,5R)-4-carboxybenzyl-5- methyloxazolidin-2-one
描述了分别含有反式-(4S,5R)-4-羧基5-甲基恶唑烷-2-酮的三个和四个残基的两个低聚物的合成。通过从苄基-N-Boc-(3R)-氨基丁酸酯开始,通过环化成相应的反-(2S,3R)-2-羧基苄基-3-甲基-N-Boc-氮丙啶和产物的重排获得单体。 Sn(OTf)2催化合成反式-(4S,5R)-4-羧基苄基-5-甲基恶唑烷丁-2-酮。通过活化羧基作为其五氟苯基酯来合成低聚物。三聚体和四聚体的收率很高,它们的1 H NMR光谱表明这些分子以有序结构折叠,其中一个环的C-4氢始终靠近下一个环的羰基。