作者:Sho Hirai、Naoko Urushizako、Masayuki Miyano、Tomohiro Fujii、Masahisa Nakada
DOI:10.1016/j.tetlet.2013.01.115
日期:2013.4
preparations of the taxol A-ring fragment are described: one via organocatalyzed α-aminoxylation and the other via Sharpless asymmetric dihydroxylation (SAD). The former approach affords the A-ring fragment in 10 steps, and the latter approach involves eight steps to afford the new A-ring fragment in 91% ee, which is made enantiomerically pure through recrystallization. The new A-ring fragment bearing a bromoalkene
描述了紫杉醇A环片段的两种简短制备方法:一种是通过有机催化的α-氨氧基化反应,另一种是通过Sharpless不对称二羟基化反应(SAD)。前一种方法分10步提供A环片段,后一种方法包括8个步骤以91%ee提供新的A环片段,通过重结晶使对映体纯。证实带有溴代烯烃的新的A-环片段可用于通过钯催化的分子内烯基化形成紫杉醇模型化合物的碳环八元环。新的A环片段的制备将有助于紫杉醇以及其他天然产物的全合成