The synthesis of chiral isopropylidene derivatives of 1,2,3-cyclohexanetriols by enzymatic differentiation
作者:L. Dumortier、J. Van der Eycken、M. Vandewalle
DOI:10.1016/s0040-4039(00)99201-3
日期:——
2,3-O-Isopropylidene-1-cyclohexanol chiral building blocks have been prepared with high enantiomeric purities by enzymatic hydrolysis of their racemic acetates or n.butyrates.
Anionic Cyclization Approach toward Perhydrobenzofuranone: Stereocontrolled Synthesis of the Hexahydrobenzofuran Subunit of Avermectin
作者:Chin-Kang Sha、Shih-Jung Huang、Zhuang-Ping Zhan
DOI:10.1021/jo010853p
日期:2002.2.1
A facile anionic cyclization approach toward stereocontrolled synthesis of the hexahydrobenzofuran subunit 3 of avermectin is described. As a model study, treatment of iodo compound 7 with n-BuLi at -100 degrees C effected metal-halogen exchange and subsequent anionic cyclization to afford perhydrobenzofuranone 8. For the total synthesis of subunit 3, compound 9 was dihydroxylated to give diol 10. Protection