光合四吡咯大环化合物的计划全合成通过已建立的不对称方法在早期前体中安装了必要的立体化学特征。关键构建模块是含有手性吡咯啉单元的二氢二吡啶,手性六-5-yn-2-酮是其有价值的前体。寻找在 1 位带有不同官能团的手性 hex-5-yn-2-one,其对应于细菌叶绿素 a 的手性吡咯啉单元(环 B 和 D )。本文报告了三个主要结果。首先,将通过Schreiber 改进的尼古拉斯反应制备的 (2 R ,3 R )-3-乙基-2-甲基戊-4-炔酸转化为类似的手性 Weinreb 戊酰胺。后者用三丁基锡-一碳合成子处理,产生 1-羟基己基-5-yn-2-酮支架,其中包含两个必需的立体中心,并具有新引入的游离形式或保护为 Me、MOM、THP 的羟基。 、MEM、Bn 或 SEM 导数。其次,在获得前 B 化合物 (3 R ,4 R )-1,1-二甲氧基-3-乙基-4-甲基己-5-yn-2-one
Synthetic studies towards the phomactins. Concise syntheses of the tricyclic furanochroman and the oxygenated bicyclo[9.3.1]pentadecane ring systems in phomactin A
作者:Kevin M Foote、Christopher J Hayes、Matthew P John、Gerald Pattenden
DOI:10.1039/b307985f
日期:——
A concise synthesis of the tricyclic furanochroman unit 3 found in the PAF antagonist phomactin A (1) isolated from the marine fungus Phoma sp., is described. In complementary studies, a variety of synthetic routes towards the bicyclo[9.3.1]pentadecaneringsystem 4 in phomactin A were explored. These studies culminated in a synthesis of the substituted ringsystem 79 containing all the carbon atoms
The synthesis and testing of configurationalstability of chirally monodeuterated PMB- and THP-substituted oxymethyllithiums are described. Macroscopically they are configurationally stable up to −35 °C, the limit of their chemical stability, and microscopically even up to 0 °C. Furthermore, THP-protected oxy-[D1]methyllithium has been applied in the formal synthesis of (6R)-[6-D1]-d-glucose (four
描述了手性单氘代PMB和THP取代的氧甲基锂的合成和构型稳定性的测试。在宏观上,它们在高达-35°C(化学稳定性的极限)下具有构型稳定性,在微观上甚至高达0°C。此外,THP-保护的氧基- [ d 1 ]甲基锂(6正式合成已施加ř) - [6- d 1 ] - d -葡萄糖(四个步骤,40%产率),作为其使用的一个例子纯手性羟甲基合成子。
Amelioration of the conjugate addition chemistry of .alpha.-alkoxycopper reagents: application to the stereospecific synthesis of C-Glycosides