Moore Rebecca E, Craft Kelly M, Xu Lianyan L, Chambers Schuyler A, Nguyen Johny M, Marion Keevan C, Gaddy Jennifer A, Townsend Steven D
Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Nashville, Tennessee 37235, United States.
Department of Medicine, Vanderbilt University Medical Center, 1161 21st Avenue South, D-3100 Medical Center North, Nashville, Tennessee 37232, United States.
J Org Chem. 2020 Dec 18;85(24):16128-16135. doi: 10.1021/acs.joc.0c01958. Epub 2020 Oct 14.
Alongside Edward, Lemieux was among the earliest researchers studying negative hyperconjugation (i.e., the anomeric effect) or the preference for gauche conformations about the C1-O5 bond in carbohydrates. Lemieux also studied an esoteric, if not controversial, theory known as the reverse anomeric effect (RAE). This theory is used to rationalize scenarios where predicted anomeric stabilization does not occur. One such example is the Kochetkov amination where reducing end amines exist solely as the β-anomer. Herein, we provide a brief account of Lemieux's contributions to the field of stereoelectronics and apply this knowledge toward the synthesis of β-amino human milk oligosaccharides (βΑ-HMOs). These molecules were evaluated for their ability to inhibit growth and biofilm production in Group B Streptococcus (GBS) and . While the parent HMOs lacked antimicrobial and antibiofilm activity, their β-amino derivatives significantly inhibited biofilm formation in both species. Field emission gun-scanning single electron microscopy (FEG-SEM) revealed that treatment with β-amino HMOs significantly inhibits bacterial adherence and eliminates the ability of both microbes to form biofilms.
与爱德华兹一起,勒米厄是最早研究负超共轭(即端基异构效应)或碳水化合物中C1 - O5键对gauche构象偏好的研究人员之一。勒米厄还研究了一种即便不是有争议的,也是深奥的理论,即反向端基异构效应(RAE)。该理论用于解释预测的端基异构稳定化未出现的情况。一个这样的例子是科切特科夫胺化反应,其中还原端胺仅以β - 端基异构体形式存在。在此,我们简要介绍勒米厄在立体电子学领域的贡献,并将这些知识应用于β - 氨基人乳寡糖(βΑ - HMOs)的合成。对这些分子抑制B族链球菌(GBS)生长和生物膜形成的能力进行了评估。虽然母体HMOs缺乏抗菌和抗生物膜活性,但其β - 氨基衍生物在两种菌中均显著抑制生物膜形成。场发射枪扫描单电子显微镜(FEG - SEM)显示,用β - 氨基HMOs处理可显著抑制细菌黏附,并消除两种微生物形成生物膜的能力。