The stereoselective addition of enantiomerically pure (as shown by 200 MHz 1H NMR study) dipeptide Boc-Cys-Ala-OMe 4 to α-methylene-γ-butyrolactones has been studied. The stereoselectivity of the addition parallels the enantioselectivity observed in the allergic contact dermatitis induced in guinea pigs.
已经研究了对映体纯(如200 MHz 1 H NMR研究所示)向α-亚甲基-γ-丁内酯中立体定向加成的二肽Boc-Cys-Ala-OMe 4。添加的立体选择性与在豚鼠诱发的过敏性接触性皮炎中观察到的对映选择性平行。
First Asymmetric Total Syntheses and Determination of Absolute Configurations of (+)-Eudesmadiene-12,6-olide and (+)-Frullanolide
作者:Yu-Yu Chou、Chun-Chen Liao
DOI:10.1021/ol4003724
日期:2013.4.5
The first asymmetric total syntheses of sesquiterpene lactones (+)-eudesmadiene-12,6-olide (1) and (+)-frullanolide (2) have been accomplished from 4-bromo-2-methoxyphenol (5) in 12 and 13 synthetic steps, respectively, and the absolute configurations of these two natural products were determined.