Abad-Romero Beatriz, Mereiter Kurt, Sixta Herbert, Hofinger Andreas, Kosma Paul
Department of Chemistry, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
Carbohydr Res. 2009 Jan 5;344(1):21-8. doi: 10.1016/j.carres.2008.09.018. Epub 2008 Sep 24.
Methyl xylobioside and methyl xylotrioside were prepared from the peracetylated anomeric xylosyl trichloroacetimidates by reaction with methanol followed by Zemplén deacetylation. Methyl beta-D-xylopyranoside, methyl beta-D-xylobioside and methyl beta-D-xylotrioside were subjected to treatment with dibutyltin oxide followed by reaction with the trimethylamine/sulfur trioxide complex in tetrahydrofuran. This way, preferential sulfation of the terminal 4-hydroxy group at the nonreducing xylopyranosyl unit was achieved. In addition, partial sulfation at position 2 of the distal xylose unit was observed. The substitution pattern was derived from NMR spectroscopic data and was confirmed by the X-ray structure determination of sodium methyl beta-D-xylopyranoside 4-O-sulfate. The compound crystallized as a hemihydrate in a triclinic lattice of space group P1 and possesses a pseudomonoclinic 2D supramolecular structure. The sulfation of free pentose oligomers via their intermediate stannylene acetals may thus be exploited to generate biologically active oligosaccharides for biomedical applications.
甲基木二糖苷和甲基木三糖苷由全乙酰化的异头木糖基三氯乙酰亚胺酯与甲醇反应，随后进行泽普林脱乙酰反应制备而成。将β-D-吡喃木糖苷甲酯、β-D-木二糖苷甲酯和β-D-木三糖苷甲酯用二丁基氧化锡处理，然后在四氢呋喃中与三甲胺/三氧化硫络合物反应。通过这种方式，实现了在非还原吡喃木糖基单元末端4-羟基的优先硫酸化。此外，还观察到远端木糖单元2位的部分硫酸化。取代模式由核磁共振光谱数据得出，并通过β-D-吡喃木糖苷甲酯4-O-硫酸盐钠的X射线结构测定得到证实。该化合物以半水合物形式结晶，属于空间群P1的三斜晶格，具有假单斜二维超分子结构。因此，通过游离戊糖寡聚物的中间亚锡缩醛进行硫酸化，可用于制备具有生物活性的寡糖，用于生物医学应用。
