Repetto Evangelina, Marino Carla, Uhrig M Laura, Varela Oscar
CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, 1428-Buenos Aires, Argentina.
Bioorg Med Chem. 2009 Apr 1;17(7):2703-11. doi: 10.1016/j.bmc.2009.02.045. Epub 2009 Feb 26.
Thiodisaccharides having beta-D-Galf or alpha-L-Araf units as non-reducing end have been synthesized by the SnCl(4)- or MoO(2)Cl(2)-promoted thioglycosylation of per-O-benzoyl-D-galactofuranose (1), its 1-O-acetyl analogue 4, or per-O-acetyl-alpha-L-arabinofuranose (16) with 6-thioglucose or 6-thiogalactose derivatives. After convenient removal of the protecting groups, the free thiodisaccharides having the basic structure beta-D-Galf(1-->6)-6-thio-alpha-D-Glcp-OMe (5) or beta-D-Galf(1-->6)-6-thio-alpha-D-Galp-OMe (15) were obtained. The respective alpha-L-Araf analogues 18 and 20 were prepared similarly from 16. Alternatively, beta-D-Galf(1-->4)-4-thio-3-deoxy-alpha-L-Xylp-OiPr was synthesized by Michael addition to a sugar enone of 1-thio-beta-d-Galf derivative, generated in situ from the glycosyl isothiourea derivative of 1. The free S-linked disaccharides were evaluated as inhibitors of the beta-galactofuranosidase from Penicillium fellutanum, being 15 and 20 the more active inhibitors against this enzyme.
以β-D-半乳呋喃糖（Galf）或α-L-阿拉伯呋喃糖（Araf）单元作为非还原端的硫代二糖，已通过用四氯化锡（SnCl₄）或二氯氧化钼（MoO₂Cl₂）促进的全-O-苯甲酰基-D-半乳呋喃糖（1）、其1-O-乙酰基类似物4或全-O-乙酰基-α-L-阿拉伯呋喃糖（16）与6-硫代葡萄糖或6-硫代半乳糖衍生物的硫代糖基化反应合成。在方便地除去保护基后，得到了具有基本结构β-D-Galf(1→6)-6-硫代-α-D-葡萄糖吡喃糖-OMe（5）或β-D-Galf(1→6)-6-硫代-α-D-半乳糖吡喃糖-OMe（15）的游离硫代二糖。相应的α-L-Araf类似物18和20由16类似地制备。另外，通过迈克尔加成到由1的糖基异硫脲衍生物原位生成的1-硫代-β-D-Galf衍生物的糖烯酮上，合成了β-D-Galf(1→4)-4-硫代-3-脱氧-α-L-木糖吡喃糖-OiPr。游离的S-连接二糖被评估为来自费鲁坦青霉的β-半乳呋喃糖苷酶的抑制剂，其中15和20是对该酶活性更高的抑制剂。
