Total Synthesis of <i>Pseudomonas aeruginosa</i> 1244 Pilin Glycan via <i>de Novo</i> Synthesis of Pseudaminic Acid
作者:Han Liu、Yanfeng Zhang、Ruohan Wei、Gloria Andolina、Xuechen Li
DOI:10.1021/jacs.7b06055
日期:2017.9.27
synthesis involve the diastereoselective glycine thioester isonitrile-based aldol-type reaction to create the 1,3-anti-diamino skeleton, followed by the Fukuyama reduction and the indium-mediated Barbier-typeallylation. Moreover, we have studied the glycosylation of the Pse glycosyl donors and identified the structural determinants for its glycosylation diastereoselectivity, which enabled us to complete
假胺酸 (Pse) 是细菌物种特有的一种非洛糖酸,是各种病原体物种中重要的细胞表面聚糖和糖蛋白的组成部分,例如对医院造成严重威胁的铜绿假单胞菌 (Pseudomonas aeruginosa)。在此,我们介绍了从容易获得的 Cbz-l-异素苏氨酸甲酯(16 个步骤,产率 11%)开发 Pse 及其功能化衍生物的简便且可扩展的从头合成。我们从头合成中的关键反应涉及基于非对映选择性甘氨酸硫酯异腈的羟醛型反应,以创建 1,3-抗二氨基骨架,然后是 Fukuyama 还原和铟介导的 Barbier 型烯丙基化。此外,我们研究了 Pse 糖基供体的糖基化,并确定了其糖基化非对映选择性的结构决定因素,
Visible‐Light Mediated Tryptophan Modification in Oligopeptides Employing Acylsilanes
作者:Jannik Reimler、Armido Studer
DOI:10.1002/chem.202102749
日期:2021.11.5
Photo click chemistry was used for the selective modification of the indole moiety in various tryptophan-containing di-, tri- and tetra-peptides. The process uses aroylsilanes as readily available reagents, that cleanly rearrange upon visiblelight irradiation to the corresponding silyloxycarbenes which in turn insert into the indole N−H bond to give stable silyl protected hemiaminals.
This application discloses a composition comprising a malodor compound and an anti-odor ingredient effective for reducing the presence or production of malodor. The composition may be topically applied to a subject and is useful for cosmetic conditions, pharmaceutical indications, or other objectives.