Liav A, Goren M B
Department of Pediatrics, National Jewish Center for Immunology and Respiratory Medicine, Denver, CO 80206.
Chem Phys Lipids. 1989 Jul;51(1):9-13. doi: 10.1016/0009-3084(89)90060-1.
Tritylation of 2,3,2',3'-tetra-O-benzyl-(alpha-D-galactopyranosyl alpha-D-galactopyranoside) (4) (A. Liav, H.M. Flowers and M.B. Goren (1984) Carbohydr. Res. 133, 53-58) followed by benzylation and acid hydrolysis gave 2,3,4,2',3',4'-hexa-O-benzyl-(alpha-D-galactopyranosyl alpha-D-galactopyranoside) (6). Triflation of 6 with triflic anhydride gave the ditriflate 7. Treatment of 7 with potassium mycolate or potassium corynomycolate in toluene, followed by catalytic hydrogenolysis afforded the respective cord-factor analogs 6,6'-di-O-mycoloyl-(alpha-D-galactopyranosyl alpha-D-galactopyranoside) (10) and 6,6'-di-O-corynomycoloyl (alpha-D galactopyranosyl alpha-D-galactopyranoside) (11). An alternative approach, based on the debenzylation of 2,3,2',3'-tetra-O-benzyl-6,6'-di-O-p-tolylsulfonyl- (alpha-D-galactopyranosyl alpha-D-galactopyranoside) (1) and conversion of the latter into the corresponding 3,4,3',4'-diisopropylidene derivative 3 failed to yield satisfactory results.
对2,3,2',3'-四-O-苄基-(α-D-吡喃半乳糖基α-D-吡喃半乳糖苷)(4)(A. 利亚夫、H.M. 弗劳尔斯和M.B. 戈伦(1984年)《碳水化合物研究》133, 53 - 58)进行三苯甲基化，随后进行苄基化和酸水解，得到2,3,4,2',3',4'-六-O-苄基-(α-D-吡喃半乳糖基α-D-吡喃半乳糖苷)(6)。用三氟甲磺酸酐对6进行三氟甲磺酰化得到二(三氟甲磺酸酯)7。在甲苯中用霉菌酸钾或棒状杆菌酸钾处理7，随后进行催化氢解，得到相应的索状因子类似物6,6'-二-O-霉菌酰基-(α-D-吡喃半乳糖基α-D-吡喃半乳糖苷)(10)和6,6'-二-O-棒状杆菌酰基(α-D-吡喃半乳糖基α-D-吡喃半乳糖苷)(11)。另一种方法是基于对2,3,2',3'-四-O-苄基-6,6'-二-O-对甲苯磺酰基-(α-D-吡喃半乳糖基α-D-吡喃半乳糖苷)(1)进行脱苄基化，并将后者转化为相应的3,4,3',4'-二异亚丙基衍生物3，但未能得到满意的结果。
