X-RAY-DIFFRACTION EVIDENCE FOR AROMATIC PI HYDROGEN-BONDING TO WATER
X-RAY-DIFFRACTION EVIDENCE FOR AROMATIC PI HYDROGEN-BONDING TO WATER
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DOI：
10.1038/349683a0
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发表时间：
1991-02-21
期刊：
影响因子：
64.8
通讯作者：
VINCENT, RL
中科院分区：
文献类型：
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作者：
ATWOOD, JL;HAMADA, F;VINCENT, RL
水与芳香族的相互作用在生物系统中是很重要的，因为大多数生物在其正常功能过程中都会遇到水环境。例如，球状蛋白质的常见成分，如苯丙氨酸、色氨酸和酪氨酸，都具有芳香侧链，可能会在蛋白质结构中遇到水分子。作为与芳烃氢键相互作用的模型，我们对Na4[杯[4]芳烃磺酸盐]晶体进行了x射线衍射研究。杯芳烃分子3,4含有由芳香基团组成的疏水空腔，在水溶性磺酸盐（R = -SO3Na）的情况下，由亲水基团5,6包围。在没有疏水客体的情况下，空腔总是含有水分子。该化合物的低温x射线晶体结构（见表1和图1）显示了固体状态下水与芳香族pi电子之间氢键的直接证据。
THE interaction of water with aromatic moieties is of importance in biological systems, as most encounter an aqueous environment during their normal functions. For example, common constituents of globular proteins such as phenylalanine, tryptophan and tyrosine possess aromatic side-chains 1 that may encounter water molecules inside the protein structure 2. As a model for hydrogen-bonding interactions with aromatics, we have performed X-ray diffraction studies on crystalline Na4[calix[4]arene sulphonate].13.5H20. Calixarene molecules 3,4 contain hydrophobic cavities comprised of aromatic groups, rimmed, in the case of the water-soluble sulphonates (R = -SO3Na), by hydrophilic groups 5,6. In the absence of a hydrophobic guest, the cavity invariably contains a water molecule. The low-temperature X-ray crystal structure of this compound (see Table 1 and Fig. 1) shows direct evidence for hydrogen bonding between water and the aromatic pi-electrons in the solid state.