3 - O - 苯甲酰基 - 4,6；4',6' - 二 - O - 亚苄基 - 2,2' - 二脱氧，α,α - 核糖型海藻糖

3-O-benzoyl-4,6;4',6'-di-O-benzylidene-2,2'-dideoxy,alpha,alpha-ribo- trehalose.

作者信息

Linden A, Lee C K

机构信息

Organisch-chemisches Institut, Universität Zürich, Switzerland.

出版信息

Acta Crystallogr C. 1995 Apr 15;51 ( Pt 4):747-51. doi: 10.1107/s010827019401440x.

DOI:10.1107/s010827019401440x

PMID:7619341

Abstract

The low-temperature X-ray structure of an asymmetrically substituted derivative of alpha,alpha-trehalose, 3-O-benzoyl-4,6;4',6'-di-O-benzylidene-2,2'-dideoxy-alpha,alpha-ribo-tre halose (3-O-benzoyl-4,6-O-benzylidene-2-deoxy-alpha-D-ribo-hexopyranosyl 4,6-O-benzylidene-2-deoxy-alpha-D-ribo-hexopyranoside, C33H34O10), is reported. The hexopyranosyl rings and the 1,3-dioxane rings have normal 4C1 chair conformations, so that each half of the molecule has a double-chair conformation, resembling a trans-decalin ring system. Each benzylidene acetal group takes the form of the thermodynamically more stable (R)-diastereomer with its phenyl group attached to the 1,3-dioxane ring in an equatorial orientation. The conformations about the glycosidic linkages are stabilized by the anomeric effect and by an intramolecular hydrogen bond between the lone hydroxy group and the glycosidic O atom.

摘要

报道了α,α-海藻糖的不对称取代衍生物3-O-苯甲酰基-4,6;4',6'-二-O-亚苄基-2,2'-二脱氧-α,α-核糖海藻糖（3-O-苯甲酰基-4,6-O-亚苄基-2-脱氧-α-D-核糖己吡喃糖基4,6-O-亚苄基-2-脱氧-α-D-核糖己吡喃糖苷，C33H34O10）的低温X射线结构。己吡喃糖环和1,3-二氧六环环具有正常的4C1椅式构象，因此分子的每一半都具有双椅式构象，类似于反式十氢化萘环系。每个亚苄基缩醛基团以热力学上更稳定的（R）-非对映异构体形式存在，其苯基以赤道取向连接到1,3-二氧六环环上。糖苷键的构象通过异头效应和孤羟基与糖苷O原子之间的分子内氢键得以稳定。