Syntheses of (+)-30-epi-, (-)-6-epi-, (±)-6,30-epi-13,14-Didehydroxyisogarcinol and (±)-6,30-epi-Garcimultiflorone A Utilizing Highly Diastereoselective, Lewis Acid-Controlled Cyclizations.
Syntheses of (+)-30-epi-, (-)-6-epi-, (±)-6,30-epi-13,14-Didehydroxyisogarcinol and (±)-6,30-epi-Garcimultiflorone A Utilizing Highly Diastereoselective, Lewis Acid-Controlled Cyclizations.
复制标题
DOI：
10.1021/jacs.6b09727
复制
发表时间：
2016-11-09
影响因子：
15
通讯作者：
Porco JA Jr
中科院分区：
文献类型：
--
作者：
Boyce JH;Eschenbrenner-Lux V;Porco JA Jr
首次报道了从市售间苯三酚经六步合成13，14-二去羟基异甘草酚（6）和garcimultiflorone A（5）立体异构体。刘易斯酸控制的、非对映选择性的阳离子氧环化使得能够不对称合成（−）-6-epi-6和（+）-30-epi-6。类似的策略使得能够产生内消旋异构体（±）-6，30-差向-6和（±）-6，30-差向-5。最后，开发了一种方便的克级合成策略，在合成的后期阶段利用非对映体分离，最大限度地减少了获得所有可能的立体异构体所需的合成操作的数量。
The first syntheses of 13,14-didehydroxyisogarcinol (6) and garcimultiflorone A (5) stereoisomers are reported in six steps from a commercially available phloroglucinol. Lewis acid-controlled, diastereoselective cationic oxycyclizations enabled asymmetric syntheses of (−)-6-epi-6 and (+)-30-epi-6. A similar strategy enabled production of the meso-dervied isomers (±)-6,30-epi-6 and (±)-6,30-epi-5. Finally, a convenient strategy for gram scale synthesis was developed utilizing diastereomer separation at a later stage in the synthesis that minimized the number of necessary synthetic operations to access all possible stereoisomers.