ω-Di-(trideuteromethyl)-tocotrienols as probes for membrane orientation and dynamics of tocotrienols
作者:Ryan West、Yongsheng Wang、Jeffrey Atkinson
DOI:10.1002/jlcr.1554
日期:2008.11
The study of the dynamic and structural role of lipids in membranes is commonly accomplished using 2H NMR and neutron diffraction. This necessarily requires the availability of specifically deuterated lipids. Our interest in the behaviour of tocopherols and tocotrienols in phospholipid membranes has shown that the tocotrienols, unsaturated forms of vitamin E, have very different effects on membrane properties as judged by differential scanning calorimetry (DSC). We report here the preparation of deuterated forms of α-, β-, and γ-tocotrienols where the terminal methyl groups on the isoprenoid side chains have been replaced with trideuteromethyl groups, thus incorporating six deuterium atoms per molecule. Starting from the naturally occurring tocotrienols, the terminal alkene can be selectively hydrobrominated with NBS, transformed to a diol and oxidatively cleaved to give a chain truncated aldehyde. The full chain length is then restored by reaction with the ylide formed by deprotonation of triphenyl-(1,2,2,2-tetradeutero-1-trideuteromethyl-ethyl)-phosphonium bromide. Copyright © 2008 John Wiley & Sons, Ltd.
研究膜中脂质的动态和结构作用通常使用 2H NMR 和中子衍射法。这必然要求有特定的氚代脂质。我们对生育酚和生育三烯酚在磷脂膜中的行为的兴趣表明,生育三烯酚是维生素 E 的不饱和形式,通过差示扫描量热法(DSC)判断,它们对膜特性的影响截然不同。我们在此报告α-、β-和γ-生育三烯酚氚化形式的制备方法,其中异戊二烯侧链上的末端甲基被三氚甲基取代,因此每个分子中含有六个氚原子。从天然存在的生育三烯酚开始,末端烯可以选择性地用 NBS 进行氢溴化,转化为二元醇,然后氧化裂解,得到截链醛。然后通过与三苯基-(1,2,2,2-四正丁氧-1-三uteromethyl-乙基)-溴化膦去质子化形成的酰亚胺反应,恢复全链长度。Copyright © 2008 John Wiley & Sons, Ltd. 版权所有。