Efficient transformation of 7,14-dihydroxy-ent-kaurenes to novel ent-abietanes having cis-fused α-methylene γ-lactones under Mitsunobu reaction conditions and their cytotoxicities
摘要:
Transformation of plant-origin 7,14-dihydroxy-ent-kaurenes to ent-abietanes having a cis-fused alpha-methylene gamma-lactones was accomplished efficiently under the Mitsunobu reaction conditions. The yields of the desired products were apparently influenced by the steric hindrance at C-1. The cytotoxic activity on P388 murine leukemia cells of the ent-abietanes having cis-fused alpha-methylene gamma-lactones produced were assayed. (C) 2014 Elsevier Ltd. All rights reserved.
Efficient transformation of 7,14-dihydroxy-ent-kaurenes to novel ent-abietanes having cis-fused α-methylene γ-lactones under Mitsunobu reaction conditions and their cytotoxicities
Transformation of plant-origin 7,14-dihydroxy-ent-kaurenes to ent-abietanes having a cis-fused alpha-methylene gamma-lactones was accomplished efficiently under the Mitsunobu reaction conditions. The yields of the desired products were apparently influenced by the steric hindrance at C-1. The cytotoxic activity on P388 murine leukemia cells of the ent-abietanes having cis-fused alpha-methylene gamma-lactones produced were assayed. (C) 2014 Elsevier Ltd. All rights reserved.
Diastereoselective Synthesis of
<i>trans</i>
‐
<i>anti</i>
‐Hydrophenanthrenes via Ti‐mediated Radical Cyclization and Total Synthesis of Kamebanin
A diastereoselective synthesis of the functionalized trans-anti-hydrophenanthrenes via Ti-mediated reductive radical cyclization has been developed. This method enabled the convergent totalsynthesis of nebularilactone A and the first totalsynthesis of kamebanin via a novel formal semi-pinacol rearrangement reaction and an unprecedented Thorpe-Ziegler-type D-ring formation reaction.
已经开发了通过 Ti 介导的还原自由基环化功能化的反式-反式 -氢菲的非对映选择性合成。该方法通过新的形式半频哪醇重排反应和前所未有的 Thorpe-Ziegler 型 D 环形成反应实现了 nebularilactone A 的收敛全合成和 kamebanin 的首次全合成。