基于油脂化学的长链二酯是潜在的有机相变材料,可方便地进行热能存储。高效和绿色方法的发展是制备这些环境友好化合物的重要要求,这些化合物也正在广泛的工业应用中。因此,在目前的工作中,在无溶剂的介质中通过离子液体催化的可分级化学酯化或酯交换反应合成了一系列二元酸酯。使起始化合物二羧酸或其甲酯与脂肪醇或胆固醇分别按1:2的比例反应,并通过FT-IR,1 H NMR和13 C NMR对合成的酯进行表征。
A simple and efficient approach for the synthesis of cholesterol esters of long-chain saturated fatty acids by using Ph3P·SO3 as a versatile organocatalyst
作者:Ayhan Yıldırım、Cansu Avcı
DOI:10.1016/j.steroids.2022.109011
日期:2022.7
these esters play an important role in cholesterol metabolism. Moreover, some of their hydroperoxide derivatives are biologically active components of minimally modified low-density lipoprotein (mmLDL). In recent years, these esters have attracted attention in many industrial and medical applications. In this study, a triphenylphosphine-sulfur trioxide adduct efficiently catalyzed the esterification
胆固醇酯是由胆固醇与含有长烃链的脂肪酸结合形成的非极性化合物。这些酯分子不参与细胞膜的组成,存在于脂滴中。由于这种形式的胆固醇可以大量包裹在脂蛋白中,因此胆固醇的运输更有效,而且这些酯类在胆固醇代谢中起着重要作用。此外,它们的一些氢过氧化物衍生物是最小修饰低密度脂蛋白 (mmLDL) 的生物活性成分。近年来,这些酯在许多工业和医疗应用中引起了人们的关注。在这项研究中,三苯基膦-三氧化硫加合物在甲苯中有效催化同源长链饱和单羧酸或二羧酸脂肪酸与胆固醇分子的酯化反应。在这些反应中,基于三苯基膦的加合物充当三氧化硫的来源。除二羧酸外,反应在 110 °C 下用等摩尔量的试剂进行,使用两个等摩尔的胆固醇以良好至优异的产率提供相应的同源胆固醇酯。目前开发的方法具有比现有方法更简单、实用、毒性更小的优点,并且能够以更高的收率合成相关酯。基于三苯膦的加合物充当三氧化硫的来源。除二羧酸外,反应在 110 °C
Thermal and optical properties of chiral twin liquid crystalline bis(cholesteryl) alkanedioates
作者:Antonius T. M. Marcelis、Arie Koudijs、Ernst J. R. Sudhölter
DOI:10.1039/jm9960601469
日期:——
The thermal and optical properties of a series of bis (cholesteryl) alkanedioates were investigated. The melting points, the cholesteric to isotropic transition temperatures, the entropy changes at this temperature and the selective reflection wavelengths of the cholesteric phase all exhibit an odd-even effect as a function of spacer length. This is attributed to a difference in the ordering of the cholesteric phase as a function of the parity of the spacer. Because the properties of the members of the series with a short spacer could not be measured for several reasons, their properties were also determined as a 5 wt% solution in a cholesteric host. A similar odd-even influence on the cholesteric to isotropic transition temperatures and the optical properties of the host was observed as for the pure compounds. The influence on the properties of the host is stronger for compounds with a short spacer than for compounds with a longer spacer.
Liquid Crystallinity of Non-Symmetrical Dimeric Compounds (I) Synthesis of 4-(4′-Benzyloxy)Biphenyl Cholesteryl Alkanedioates and their Phase Transition Behavior