Sphingolipids and Glycerolipids. IV. Syntheses and Ionophoretic Activities of Several Analogues of Soya-cerebroside II, a Calcium Ionophoretic Sphingoglycolipid Isolated from Soybean.
作者:Hirotaka SHIBUYA、Michio KUROSU、Kazuyuki MINAGAWA、Seiji KATAYAMA、Isao KITAGAWA
DOI:10.1248/cpb.41.1534
日期:——
For examination of the structure-activity relationship five analogues [(2'R)-2'-hydroxypalmitoyl (3), palmitoyl (4), (2'S)-2'-hydroxypalmitoyl (5), β-D-galactosyl (6), and 8, 9-dihydro (7) relevancies] of soya-cerebroside II (2), which is a calcium ionophoretic sphingoglycolipid isolated from soybean, have been synthesized by using our previously reported synthetic method for sphingoglycolipids. Examinations by using a W-08 (liquid-membrane type) apparatus and by means of the human erythrocyte membrane method, have shown that the (2'R)-2'-hydroxypalmitoyl analogue (3) exhibits higher ion-binding and ion-permeation activities for calcium ion than soya-cerebroside II (2), which contains 3 as the major component. It has also been found that the other analogues(5, 6, 7, 8) do not show those ionophoretic activities.An enantiomer (8) of the (2'R)-2'-hydroxypalmitoyl analogue (3) has been synthesized and its calcium ionophoretic activity examined. Compound 8 exhibits calcium ion-binding activity equal to that of 3, but 8 lacks the ability to support calcium ion-permeation through human erythrocyte membrane. Thus, human erythrocyte membrane precisely distinguishes the absolute configurations of 3 and 8 as regards calcium ionophoretic activity.
为了研究结构-活性关系,我们利用先前报道的鞘糖脂合成方法,合成了大豆神经酰胺II(2)的五种类似物[(2'R)-2'-羟基棕榈酰(3)、棕榈酰(4)、(2'S)-2'-羟基棕榈酰(5)、β-D-半乳糖基(6)和8, 9-二氢(7)相关物],2是从大豆中分离出的钙离子载体鞘氨醇糖脂。通过使用W-08(液膜型)装置和人体红细胞膜方法的检测表明,(2'R)-2'-羟基棕榈酰类似物(3)对钙离子的离子结合和离子渗透活性高于以3为主要成分的大豆神经酰胺II(2)。还发现其他类似物(5, 6, 7, 8)没有那些离子载体活性。合成了(2'R)-2'-羟基棕榈酰类似物(3)的对映体(8),并检测了其钙离子载体活性。化合物8显示出与3相等的钙离子结合活性,但8缺乏支持钙离子通过人体红细胞膜的能力。因此,人体红细胞膜在钙离子载体活性方面精确区分了3和8的绝对构型。