作者:Stephen G. Davies、Ai M. Fletcher、Linlu Lv、Paul M. Roberts、James E. Thomson
DOI:10.1016/j.tetlet.2012.04.025
日期:2012.6
The asymmetric synthesis of (−)-(R)-sitagliptin was achieved in seven steps from commercially available starting materials using the highly diastereoselective conjugate additions of either lithium (R)-N-benzyl-N-(α-methylbenzyl)amide or lithium (R)-N-benzyl-N-(α-methyl-p-methoxybenzyl)amide to tert-butyl 4-(2′,4′,5′-trifluorophenyl)but-2-enoate to install the correct stereochemistry. Subsequent sequential
(-)-(R)-西他列汀的不对称合成是使用锂(R)-N-苄基-N-(α-甲基苄基)酰胺或锂的高度非对映选择性共轭物,从市售原料中分七个步骤完成的(R)-N-苄基-N-(α-甲基-对甲氧基苄基)酰胺成4-(2',4',5'-三氟苯基)丁-2-烯酸叔丁酯以安装正确的立体化学。随后的顺序酸催化水解所得β-氨基酯,HOBt / EDC介导的三唑并吡嗪片段偶联以及氢解得到(-)-(R-西他列汀的总产率分别为43%和42%。