Structure of 1,2,3,4,5,6-hexa-O-acetyl-myo-inositol.
Structure of 1,2,3,4,5,6-hexa-O-acetyl-myo-inositol.
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1,2,3,4,5,6-六-O-乙酰基肌醇的结构。
DOI：
10.1107/s010827019000230x
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Younathan,ES
中科院分区：
文献类型：
--
作者：
Abboud,KA;Simonsen,SH;Voll,RJ;Younathan,ES
C18H24O12，Mr= 432-4，单斜晶系，Cc，a= 8.996（3），B= 20-890（6），c= 11.872（4）A，fl= 101-11（2），V= 2189（1）A3，z= 4，Ox= 1.312 g cm-3，Mo Kte，A= 0.71069 A，lx = 1.05 cm-1，F（000）= 912，T= 163 K，R= 0.041，wR= 0-0375，对于2158次反射（Fo-> 6 o '[Fol]）。该环为椅式构象，具有5个赤道基团和1个轴向基团与C（2）键合。乙酸酯基在2、4、5和6位上的羰基键与它们各自的环C-H键大致共面。然而，在位置1和3的那些被旋转朝向H（2）原子。本研究的母体化合物肌醇具有两种不同的椅式构象：一种是较稳定的，具有5个羟基平卧和1个羟基轴向（5e/la），另一种是具有5个羟基轴向和1个羟基平卧（5a/le）。肌醇的晶体结构已被报道，不对称单元中的两个分子以5e/la构象存在，与完美的椅子形式只有一个小的变形（Rabinowitz和Kraut，1964）。肌醇衍生物的生理重要性的证据正在迅速积累。这些衍生物已被证明是许多过程的第二信使（Pelech &万斯，1989）和细胞表面锚（Ferguson &威廉姆斯，1988）。这些系统中的大多数是磷酸酯，其可以具有连接在不同位置的脂质基团，从而增加可能的异构体的数量并为活性效应物提供不同的构象。在单个轴向羟基上的空间大基团的存在预计将改变椅子的构象分布，以便将大基团定向到赤道位置。如果其他基团位于五个轴向羟基中的任何一个上，则分布将受到进一步的扭曲，这取决于所有轴向羟基的空间和离子性质。
Ci8H24012, Mr= 432-4, monoclinic, Cc, a= 8.996 (3), b= 20-890 (6), c= 11.872 (4) A, fl= 101-11 (2), V= 2189 (1) A3, z= 4, Ox= 1.312 g cm-3, Mo Kte, A= 0.71069 A,/x= 1.05 cm-l, F (000)= 912, T= 163 K, R= 0.041, wR= 0-0375 for 2158 reflections (Fo-> 6o'[Fol). The ring is in the chair conformation 4C~ with five equatorial groups and one axial group bonded to C (2) as expected. The carbonyl bonds of the acetate groups at positions 2, 4, 5 and 6 are approximately coplanar with their respective ring C--H bonds. However, those at positions 1 and 3 are rotated towards the H (2) atom.Introduction. The parent compound of this study, myo-inositol, has a configuration such that two dif-ferent chair conformations are possible: one, the more stable, with five hydroxyl groups equatorial and one hydroxyl axial (5e/la), and the other with five hydroxyls axial and one hydroxyl equatorial (5a/le). The crystal structure of myo-inositol has been reported and the two molecules in the asym-metric unit exist in the 5e/la conformation with only one small distortion from the perfect chair form (Rabinowitz & Kraut, 1964). Evidence of the physio-logical importance of myo-inositol derivatives is rapidly accumulating. These derivatives have been shown to act as second messengers of many pro-cesses (Pelech & Vance, 1989) and as cell-surface anchors (Ferguson & Williams, 1988). The majority of these systems are phosphate esters which may have lipid groups attached at various positions, con-sequently increasing the number of possible isomers and providing diverse conformations for the active effectors. The presence of a sterically large group on the single axial hydroxyl group would be expected to change the conformational distribution of the chair so as to orient the large group into the equatorial position. If other groups were located on any of the five now axial hydroxyl groups the distribution would then be subject to further distortion depend-ing on the steric and ionic properties of all the