Synthesis of heteroanalogues of disaccharides as potential inhibitors of the processing mannosidase Class I enzymes
摘要:
Three disaccharide analogues of alpha-D -Man-(l-->2)-alpha-D-Man-OMe in which the ring and/or glycosidic oxygen atoms have been replaced by sulfur have been synthesized as potential inhibitors of Class I mannosidase enzymes. Glycosylation of appropriately protected methyl alpha-D-mannopyranosides, having free alcohol or thiol functional groups at the 2-position, with 2,3,4,6-tetra-O-acetyl-5-thio-alpha-D-mannopyranosyl trichloroacetitmidate was selective for the synthesis of cr-linked disaccharides in the case of the 2-alcohols, but yielded an alpha/beta mixture in the case of the 2-thiol glycosyl accepters. A disaccharide containing a single sulfur in the linkage was synthesized by nucleophilic substitution of the 2-triflate of a methyl alpha-D-glucopyranoside derivative by the thiolate anion of 2,3,4,6-tetra-O-acetyl-1-thio-alpha-D-mannopyranose. Protecting groups were removed by standard methods to give the free heterosubstituted disaccharides. (C) 1998 Elsevier Science Ltd. All rights reserved.
Synthesis of heteroanalogues of disaccharides as potential inhibitors of the processing mannosidase Class I enzymes
摘要:
Three disaccharide analogues of alpha-D -Man-(l-->2)-alpha-D-Man-OMe in which the ring and/or glycosidic oxygen atoms have been replaced by sulfur have been synthesized as potential inhibitors of Class I mannosidase enzymes. Glycosylation of appropriately protected methyl alpha-D-mannopyranosides, having free alcohol or thiol functional groups at the 2-position, with 2,3,4,6-tetra-O-acetyl-5-thio-alpha-D-mannopyranosyl trichloroacetitmidate was selective for the synthesis of cr-linked disaccharides in the case of the 2-alcohols, but yielded an alpha/beta mixture in the case of the 2-thiol glycosyl accepters. A disaccharide containing a single sulfur in the linkage was synthesized by nucleophilic substitution of the 2-triflate of a methyl alpha-D-glucopyranoside derivative by the thiolate anion of 2,3,4,6-tetra-O-acetyl-1-thio-alpha-D-mannopyranose. Protecting groups were removed by standard methods to give the free heterosubstituted disaccharides. (C) 1998 Elsevier Science Ltd. All rights reserved.
X-ray fluorescence (XRF) spectrometry has been used for detecting binding events and measuring binding selectivities between chemicals and receptors. XRF may also be used for estimating the therapeutic index of a chemical. For estimating the binding selectivities of a chemical versus chemical analogs, for measuring post translational modification of proteins, and for drug manufacturing.
X 射线荧光 (XRF) 光谱法已被用于检测化学物质与受体之间的结合事件和测量结合选择性。XRF 还可用于估算化学品的治疗指数。XRF 还可用于估算化学品的治疗指数、估算化学品与化学类似物的结合选择性、测量蛋白质的翻译后修饰以及药物生产。
Synthesis and binding affinity analysis of α1-2- and α1-6- O / S -linked dimannosides for the elucidation of sulfur in glycosidic bonds using quartz crystal microbalance sensors
The role of sulfur in glycosidic bonds has been evaluated using quartz crystal microbalance methodology. Synthetic routes towards alpha 1-2- and alpha 1-6-linked dimannosides with S-or O-glycosidic bonds have been developed, and the recognition properties assessed in competition binding assays with the cognate lectin concanavalin A. Mannose-presenting QCM sensors were produced using photoinitiated, nitrenemediated immobilization methods, and the subsequent binding study was performed in an automated flow-through instrumentation, and correlated with data from isothermal titration calorimetry. The recorded Kd-values corresponded well with reported binding affinities for the O-linked dimannosides with affinities for the alpha 1-2-linked dimannosides in the lower micromolar range. The S-linked analogs showed slightly disparate effects, where the alpha 1-6-linked analog showed weaker affinity than the O-linked dimannoside, as well as positive apparent cooperativity, whereas the alpha 1-2-analog displayed very similar binding compared to the O-linked structure. (C) 2017 Elsevier Ltd. All rights reserved.