Organocatalytic Enantioselective Pictet–Spengler Reaction of α‐Ketoesters: Development and Application to the Total Synthesis of (+)‐Alstratine A
作者:Rémi Andres、Fenggang Sun、Qian Wang、Jieping Zhu
DOI:10.1002/anie.202213831
日期:2023.1.2
The reaction of tryptamine with α-ketoesters in the presence of a catalytic amount of a chiral alanine-derived squaramide and 4-nitrobenzoic acid afforded the corresponding 1-alkyl-1-methoxycarbonyl tetrahydro-β-carbolines (THBCs) in high yields and ee values. A concise seven-step asymmetric total synthesis of alstratine A, a cagelike hexacyclic indole alkaloid, was developed featuring this enantioselective
在催化量的手性丙氨酸衍生角酰胺和 4-硝基苯甲酸存在下,色胺与 α-酮酯反应得到相应的 1-烷基-1-甲氧基羰基四氢-β-咔啉 (THBC),产率和ee值。笼状六环吲哚生物碱 alstratine A 的简明七步不对称全合成以这种对映选择性 Pictet-Spengler 反应为关键步骤。