【摘要】 <正> 约30年前,Stephenson,Zemplen和Laszlo,以及Hess和Messmer.都曾應用了相似的方法,裂得欺脂酸-α-D-葡萄糖五酯.但在他们的报告里,这同一化合物的熔点并不一致,且有相當大的差異.我們認爲他们报告的熔點之所以不一致,乃是由於他們獲得了不同的同質多晶體.本文所報告的工作,證實了這一点.更多还原

【Abstract】 Polymorphism of α-D-glucose pentapalmitate has been studied by the comparison of melting points of different crystalline forms obtained under different conditions,by the determination of transition points,and by the observation of cooling and heating curves of the penta-ester.From these investigations,it has been shown at least four polymorphic forms exist in the case of α-D-glucose pentapalmitate:Form I,II,III,and IV,melting at 61.2°,66.4°,70.7°,and 75.4℃ respectively. Among these four forms, Ⅰand Ⅲ are stable crystalline forms which can be obtained directly by recrystallization under different conditions. Form Ⅱand Ⅳ have not been obtained by recrystallization in this investigation and their existence is inferred from the determination of transition points and from the observation of cooling and heating curves.更多还原