Princey Raju, Chunhua Dong, Craig R Garen, Michael T Woodside, Christopher W Cairo
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引用次数: 0
Abstract
The synthesis of neoglycoconjugates has paved the way for the discovery of novel probes that mimic natural glycoconjugates and can provide designed research tools and therapeutics. In some cases, the target protein may not be amenable to harsh conditions; therefore, semisynthetic or chemical methods must be chosen with care. Here, we present a simple and modular chemoselective coupling strategy between an unprotected sugar and an N,O-disubstituted hydroxylamine under mild acidic conditions. This strategy removes any need for protecting groups on the glycan. The terminal alkene group of the conjugate serves as an effective handle to allow facile conjugation to the protein of interest via thiol-ene coupling (TEC), with proteins bearing a cysteine or free thiol to prepare neoglycoconjugates. We demonstrate that the strategy is compatible with both N- and O-linked glycans using protecting-group free strategies and optimize the TEC conditions using a variety of photocatalysts. Finally, we test the method on an aggregation-prone protein, α-synuclein. We envision that this strategy could allow the construction of complex glycoconjugates for biological testing using isolated glycans, or for generation of conjugates where the protein of interest is sensitive to harsh conditions.
新糖缀合物的合成为发现模仿天然糖缀合物的新型探针铺平了道路,并可以提供设计的研究工具和治疗方法。在某些情况下,目标蛋白可能无法适应恶劣条件;因此,必须谨慎选择半合成或化学方法。在这里,我们提出了一个简单和模块化的化学选择性偶联策略之间的无保护的糖和N, o -二取代羟胺在温和的酸性条件下。这种策略消除了聚糖上保护基团的任何需要。缀合物的末端烯烃基团作为一个有效的手柄,允许通过巯基偶联(TEC)与感兴趣的蛋白质轻松结合,与含有半胱氨酸或游离巯基的蛋白质结合以制备新糖缀合物。我们使用无保护基团的策略证明了该策略与N-和o -链聚糖兼容,并使用多种光催化剂优化了TEC条件。最后,我们在易于聚集的蛋白α-synuclein上测试了该方法。我们设想这种策略可以允许构建复杂的糖缀合物,用于使用分离的聚糖进行生物学测试,或者用于产生对恶劣条件敏感的蛋白质的缀合物。
期刊介绍:
Bioconjugate Chemistry invites original contributions on all research at the interface between man-made and biological materials. The mission of the journal is to communicate to advances in fields including therapeutic delivery, imaging, bionanotechnology, and synthetic biology. Bioconjugate Chemistry is intended to provide a forum for presentation of research relevant to all aspects of bioconjugates, including the preparation, properties and applications of biomolecular conjugates.