Highly EnantioselectiveMethanolysis of<i>Meso</i>-Cyclic Anhydride Mediated by Bifunctional Thiourea Cinchona Alkaloid Derivatives: Access to Asymmetric Total Synthesis of (+)-Biotin
作者:Fei Xiong、Fang-Jun Xiong、Wen-Xue Chen、Hui-Qing Jia、Fen-Er Chen
DOI:10.1002/jhet.1512
日期:2013.7
asymmetric total synthesis of (+)−biotin (1) via the Hoffmann–Roche lactone–thiolactone strategy has been accomplished from commercially available cis‐1,3‐dibenzyl‐2‐imidazolidone‐4,5‐dicarboxylic acid (2). Strategic transformations include a cinchona alkaloid‐based bifunctional thiourea mediated methanolytic desymmetrization of prochiral cyclic anhydride 3 to produce the enantiomerically enriched precursor
通过Hoffmann-Roche内酯-硫代内酯策略对(+)-生物素(1)进行对映选择性不对称全合成,已从可商购的顺式-1,3-二苄基-2-咪唑啉酮-4,5-二羧酸完成(2) 。战略转型包括基于金鸡纳生物碱的双官能硫脲介导手性环酐3的甲醇脱对称,以生产对映异构体富集的罗氏内酯5的前体,以及通过格氏试剂在罗氏硫代内酯6的C-4位置引入4-羧基丁基侧链的改进方法。反应。