Synthesis of extended spacer-linked neooligodeoxysaccharides by metathesis olefination and evaluation of their RNA-binding properties
摘要:
The preparation of linear 1,4-butanediol-linked oligodeoxysugars 50-53, 58 and 60 is described which are potential binders to polynucleotides. Various aminodeoxymonosaccharides 9, 13-18, 30, 31 and 40-42 which are either allylated at the anomeric center or at C4 were subjected to the metathesis olefination protocol. Depending on the position of allylation E/Z-mixtures of C-2-symmetric head-to-head or tail-to-tail homodimers were formed. Among them, saccharides 13, 30, 31 and 40 were transformed into the corresponding 1,4-butanediol linked disaccharides 50-53 by catalytic hydrogenation of the central olefinic double bond and exhaustive deprotection. In order to target extended spacer-linked neooligosaccharides homodimeric aminoglycoside 37 was bisallylated and subjected to cross metathesis conditions using methyl 4-O-allyl daunosamide 40 as reaction partner which yielded two desired trimeric and tetrameric linearly spacer-linked daunosamine derivatives. After hydrogenation and deprotection two additional probes 58 and 60 for nucleic acid binding studies were at hand. (C) 2004 Elsevier Ltd. All rights reserved.
A new concept for immobilisingGrubbs III catalyst by direct coordination of ruthenium to polyvinyl pyridine (PVP) is presented. PVP was prepared by precipitation polymerisation, which led lo small bead sizes (0.2-2 μm) and large surface areas. Compared to commercial resins, this phase showed superior properties when employed in model ring-closing metathesis (RCM) and in representative RCM. enyne and
提出了一种通过将钌直接配位到聚乙烯基吡啶 (PVP) 来固定 Grubbs III 催化剂的新概念。PVP 是通过沉淀聚合制备的,这导致小珠尺寸 (0.2-2 μm) 和大表面积。与商业树脂相比,该相在模型闭环复分解 (RCM) 和代表性 RCM 中使用时显示出优异的性能。烯炔和 CM 与各种底物的反应。固定化的概念也适用于由玻璃聚合物复合材料制成的拉西环,可以将其纳入连续流动过程的设备中。