Crystallization and Polymorphism of 1,3‐Acyl‐Palmitoyl‐
<i>rac</i>
‐Glycerols
作者:R. John Craven、Robert W. Lencki
DOI:10.1007/s11746-011-1769-0
日期:2011.8
Crystallization and melting behavior, small‐angle X‐ray scattering, X‐ray powder diffraction and infra‐red absorbance were measured for nine 1,3‐acyl‐palmitoyl‐rac‐glycerols (1,3‐acetoyl‐, ‐butyroyl‐, ‐hexanoyl‐, ‐octanoyl‐, ‐decanoyl‐, ‐lauroyl, ‐myristoyl‐ and ‐oleoyl‐palmitoyl‐rac‐glycerol and 1,3‐dipalmitoyl‐glycerol). All but one of the prepared 1,3‐diacylglycerols (1,3‐DAG) were β‐stable with
九个1,3-酰基棕榈测量结晶和熔化行为,小角度X射线散射,X射线粉末衍射和红外吸收外消旋-glycerols(1,3- acetoyl-,-butyroyl-,己酰基,辛酰基,癸酰基,月桂酰基,肉豆蔻酰基和油酰基-棕榈酰基-外消旋甘油和1,3-二棕榈酰基-甘油)。但所有的一个制备的1,3-二酰基甘油(1,3-DAG)是β稳定与1,3- acetoyl棕榈外消旋甘油例外(β'稳定)。小角X射线散射表明,趋于β的二酸1,3-DAG中的分子采用类似于单酸1,3-DAG的人字形构型。在这种构型中,相同长度的酰基链缔合并且末端甲基之间的规则链端匹配描绘了薄片。相反,在结晶1,3- acetoyl棕榈分子外消旋-甘油取向类似于1(3)的-monoacylglycerol。有趣的是,DSC曲线表明这9种二酸化合物中有5种具有亚稳态形式-建议这些形式在1,3-DAG二酸中很常见。亚稳定形式在熔解曲线观察到当酰基链之间的长度差大(1