Synthetic Studies towards Pentacyclic Quassinoids: Total Synthesis of Unnatural (−)-14-epi-Samaderine E and Natural (−)-Samaderine Y from (S)-(+)-Carvone
作者:Tony K. M. Shing、Ying-Yeung Yeung
DOI:10.1002/chem.200600669
日期:2006.11.6
First totalsyntheses of unnatural (-)-14-epi-samaderine E (5) and natural (-)-samaderine Y (2) were accomplished from (S)-(+)-carvone (6) in 18 and 21 steps, respectively. The syntheses are short, efficient (with an average yield of 80 % plus for each transformation), enantiospecific, and produce nine new chiral centers. The crucial points of the syntheses included a regioselective allylic oxidation
Total Synthesis of (−)-Samaderine Y from (S)-(+)-Carvone
作者:Tony K. M. Shing、Ying Y. Yeung
DOI:10.1002/anie.200502763
日期:2005.12.9
Synthetic studies towards pentacyclic quassinoids: Facile and stereocontrolled construction of the E ring
作者:Tony K.M. Shing、Xue Y. Zhu、Thomas C.W. Mak
DOI:10.1016/0957-4166(96)00062-6
日期:1996.3
The CE ring 15 of the pentacyclic quassinoid skeleton is fabricated from (S)-carvone involving regioselective bishydroxylmethylation, acetonation, stereocontrolled epoxidation and epoxymethano-bridge formation, selective protection, deprotection, and oxidation. (C) 1996 Elsevier Science Ltd