Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
Carbohydr Res. 2013 Oct 18;380:1-8. doi: 10.1016/j.carres.2013.06.023. Epub 2013 Jul 6.
The torsion angle around the N-glycoprotein linkage region (GlcNAc-Asn) is an important factor for presenting sugar on the cell surface which is crucial for many biological processes. Earlier studies using model and analogs showed that this important torsion angle is greatly influenced by substitutions in the sugar part. In the present work, uronic acid alkanamides and triazole derivatives have been designed and synthesized as newer analogs of N-glycoprotein linkage region to understand the influence of the carboxylic group on linkage region torsion as well as on molecular packing. Crystal structure of N-(β-D-galacturonopyranosyl)acetamide is solved with the space group of P22121. Comparison of the torsion angle and molecular packing of this compound with N-(β-D-galactopyranosyl)acetamide showed that changing the C6-hydoxymethyl group to the carboxylic acid group has minimum influence on the N-glycosidic torsion angle, ΦN and significant influence on the molecular packing.
糖基化连接区（GlcNAc-Asn）的扭转角是影响细胞表面糖展示的重要因素，而糖展示对于许多生物过程至关重要。早期使用模型和类似物的研究表明，这个重要的扭转角受糖部分取代的影响很大。在本工作中，设计并合成了糖醛酸烷酰胺和三唑衍生物作为 N-糖基化连接区的新型类似物，以了解羧酸基团对连接区扭转以及分子堆积的影响。用 P22121 空间群解决了 N-(β-D-半乳糖吡喃糖苷基)乙酰胺的晶体结构。将该化合物与 N-(β-D-半乳糖吡喃糖苷基)乙酰胺的扭转角和分子堆积进行比较表明，将 C6-羟甲基基团变为羧酸基团对 N-糖苷扭转角 ΦN 的影响最小，但对分子堆积的影响显著。
