GLYCOSYLIDENE CARBENES .10. REGIOSELECTIVE GLYCOSIDATION OF 4,6-O-BENZYLIDENE-D-ALTROPYRANOSIDES
GLYCOSYLIDENE CARBENES .10. REGIOSELECTIVE GLYCOSIDATION OF 4,6-O-BENZYLIDENE-D-ALTROPYRANOSIDES
复制标题
DOI：
10.1002/hlca.19920750816
复制
发表时间：
1992-01-01
影响因子：
1.8
通讯作者：
VASELLA, A
中科院分区：
文献类型：
--
作者：
BOZO, E;VASELLA, A
二醇2的二嗪1、三氯乙酸酯4和溴化5具有分子内氢键(HO-C(3)到O-C(1))，在溶液中（而不是在固态中）进行糖苷化，具有高的互补区域选择性。从2和1中，人们得到的主要是1,2连接的双糖10和11 (β - d > α - d)，以及1,3连接的异构体12和13 (α - d > β - d; 1,2-/1,3连接的产物约为9:1)，去甲基化的1,3连接的双糖24-27，三糖19-22，内酯嘧啶23和羟基葡聚糖18，而2与4或5反应得到的主要是1,3连接的双糖（1,2-/1,3连接的产物约为1:9）。该双糖还被表征为醋酸酯（- >14- 17,28 -31）。产率和立体选择性取决于给体、化学计量、溶剂、温度和浓度。1,3链双糖与1糖化得到三糖19-22。β - d -altro-二醇3与1的反应以1:1的比例得到1,2-和1,3-连接的双糖32/33和34/35，表征为醋酸酯36-39，而根据Lemieux与5的糖苷化进行区域选择性（1,2-/1,3-连接产物91:9）。单醛酸酯6和7与1反应，得到甲基化双糖的40/41和42/43的端粒对；未观察到氧烷44和氧烷45。
Glycosidation by the diazirine 1, the trichloroacetimidate 4, and the bromide 5 of the altro-diol 2, possessing an intramolecular H-bond (HO-C(3) to O-C(l)) in solution, but not in the solid state, proceeds with high and complementary regioselectivity. From 2 and 1, one obtains mostly the 1,2-linked disaccharides 10 and 11 (beta-D > alpha-D), together with the 1,3-linked isomers 12 and 13 (alpha-D > beta-D; 1,2-/1,3-linked products ca. 9: 1), the demethylated 1,3-linked disaccharides 24-27, the trisaccharides 19-22, the lactone azines 23, and the hydroxyglucal 18, while 2 reacted with 4 or 5 to yield mostly the 1,3-linked disaccharides (1,2-/1,3-linked products ca. 1:9). The disaccharides were additionally characterized as acetates (-->14-17, 28-31). Yields and stereoselectivity depended upon the donor, stoichiometry, solvent, temperature, and concentration. Glycosidation of the 1,3-linked disaccharides with 1 yielded the trisaccharides 19-22. Reaction of the beta-D-altro- diol 3 with 1 gave the 1,2- and 1,3-linked disaccharides 32/33 and 34/35 in a 1:1 ratio, characterized as the acetates 36-39, while glycosidation with 5 according to Lemieux proceeded regioselectively (1,2-/1,3-linked products 91:9). The monotosylates 6 and 7 reacted with 1 to yield the anomeric pairs 40/41, and 42/43 of the tosylated disaccharides; the oxiranes 44 and 45 were not observed.