Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland.
J Biomol Struct Dyn. 2020 Jul;38(11):3359-3370. doi: 10.1080/07391102.2019.1656670. Epub 2019 Aug 30.
Furanoses are an important group of natural saccharides as well as the components of crucial biomolecules such as nucleic acids. Contrary to pyranoses, they exhibit much larger inherent flexibility which amplifies the difficulty in determining their conformational preferences. We carried out a series of molecular dynamics simulations oriented at systematic analysis of conformational properties of unfunctionalized furanose monosaccharides (all members of d-aldopento- and d-aldotetrofuranoses). The results concern the description of the influence of the ring substituents (with respect of their type, location and orientation) on the geometry of the furanose ring. The main energetic contributions to the barriers on the pseudorotation path are associated with the following types of interactions: (i) unfavorable interactions between uniformly oriented vicinal ring substituents; (ii) unfavorable -axial interactions between uniformly oriented non-vicinal ring substituents; (iii) -anomeric effect. The interactions resulting from the presence of the particular ring substituents are not additive and cannot be used to obtain the pseudorotational profiles. The orientation of the hydroxymethyl group and the conformation of the ring are not mutually correlated. Contrary, the ring conformational preferences are correlated with the orientation of the lactol group the influence of the -anomeric effect. Finally, analogously to pyranoses, also in the case of furanoses, the intramolecular hydrogen bonding does not play any essential role in conformational properties of monosaccharides.Communicated by Ramaswamy H. Sarma.
呋喃糖是一类重要的天然糖，也是核酸等关键生物分子的组成部分。与吡喃糖不同，它们表现出更大的固有灵活性，这增加了确定其构象偏好的难度。我们进行了一系列分子动力学模拟，旨在系统分析未功能化呋喃单糖（d-醛戊糖和 d-醛四呋喃糖的所有成员）的构象性质。结果涉及描述环取代基（相对于其类型、位置和取向）对呋喃糖环几何形状的影响。伪旋转路径上能垒的主要能量贡献与以下类型的相互作用有关：（i）相邻环取代基均匀取向的不利相互作用；（ii）非相邻环取代基均匀取向的不利 -轴向相互作用；（iii）-端基效应。由于特定环取代基的存在而产生的相互作用不是加和的，并且不能用于获得伪旋转轮廓。羟甲基的取向和环的构象没有相互关联。相反，环构象偏好与内消旋基团的取向相关——-端基效应的影响。最后，与吡喃糖类似，在呋喃糖的情况下，分子内氢键在单糖的构象性质中也没有任何重要作用。由 Ramaswamy H. Sarma 传达。
