4-O-β-D-吡喃半乳糖基-α-D-吡喃半乳糖苷丙酯的合成研究

Studies on the synthesis of propyl 4-O-beta-D-galactopyranosyl-alpha-D-galactopyranoside.

作者信息

El-Shenawy H A, Schuerch C

出版信息

Carbohydr Res. 1984 Aug 15;131(2):227-38. doi: 10.1016/0008-6215(84)85244-1.

Abstract

2-O-Benzoyl-3,6-di-O-benzyl-4-O-(chloroacetyl)-, 4-O-acetyl-2-O-benzoyl-3,6-di-O-benzyl-, and 2-O-benzoyl-3,4,6-tri-O-benzyl-alpha-D-galactopyranosyl chloride were converted into the corresponding 2,2,2-trifluoroethanesulfonates, and these were treated with allyl 2-O-benzoyl-3,6-di-O-benzyl-alpha-D-galactopyranoside, to give allyl 2-O-benzoyl-4-O-[2-O-benzoyl-3,6-di-O-benzyl-4-O-(chloroacetyl)- beta-D-galactopyranosyl]-3,6-di-O-benzyl-alpha-D-galactopyranoside (26; 41% yield), allyl 4-O-(4-O-acetyl-2-O-benzoyl-3,6-di-O-benzyl-beta-D- galactopyranosyl)-2-O-benzoyl-3,6-di-O-benzyl-alpha-D-galactopyranoside (27; 62% yield), and allyl 2-O-benzoyl-4-O-(2-O-benzoyl-3,4,6-tri-O-benzyl-beta-D- galactopyranosyl)-3,6-di-O-benzyl-alpha-D-galactopyranoside (28; 65% yield). All disaccharides were free from their alpha anomers. Disaccharides 26 and 27 were found to be base-sensitive, and were de-esterified by KCN in aqueous ethanol, and debenzylated with H2-Pd. Attempts to produce (1----4)-beta-D-galactopyranosides from the coupling of a number of fully esterified D-galactopyranosyl sulfonates to allyl 2,3,6-tri-O-benzoyl-alpha-D-galactopyranoside were unsuccessful.

摘要

2-O-苯甲酰基-3,6-二-O-苄基-4-O-(氯乙酰基)-、4-O-乙酰基-2-O-苯甲酰基-3,6-二-O-苄基-和2-O-苯甲酰基-3,4,6-三-O-苄基-α-D-吡喃半乳糖基氯被转化为相应的2,2,2-三氟乙烷磺酸盐，然后将这些磺酸盐与烯丙基2-O-苯甲酰基-3,6-二-O-苄基-α-D-吡喃半乳糖苷反应，得到烯丙基2-O-苯甲酰基-4-O-[2-O-苯甲酰基-3,6-二-O-苄基-4-O-(氯乙酰基)-β-D-吡喃半乳糖基]-3,6-二-O-苄基-α-D-吡喃半乳糖苷(26；产率41%)、烯丙基4-O-(4-O-乙酰基-2-O-苯甲酰基-3,6-二-O-苄基-β-D-吡喃半乳糖基)-2-O-苯甲酰基-3,6-二-O-苄基-α-D-吡喃半乳糖苷(27；产率62%)和烯丙基2-O-苯甲酰基-4-O-(2-O-苯甲酰基-3,4,6-三-O-苄基-β-D-吡喃半乳糖基)-3,6-二-O-苄基-α-D-吡喃半乳糖苷(28；产率65%)。所有二糖均不含其α异头物。发现二糖26和27对碱敏感，在乙醇水溶液中被KCN脱酯，并用H2-Pd脱苄基。尝试通过将多种完全酯化的D-吡喃半乳糖基磺酸盐与烯丙基2,3,6-三-O-苯甲酰基-α-D-吡喃半乳糖苷偶联来制备(1→4)-β-D-吡喃半乳糖苷未成功。