一种新的保护的2-脱氧-2-氨基葡二糖合成

Syntheses of New Protected 2-Deoxy-2-amino Diglucose

以氨基葡萄糖盐酸盐为原料制得糖基给体 3 ,4,6 三 -氧 -乙酰 2 脱氧 2 ( 2 ,2 ,2 三氯乙氧 )甲酰胺基 α D 吡喃葡萄糖基三氯乙酰亚胺酯 ( 5 )和糖基受体烯丙基 4,6 氧 -亚苄基 2 脱氧 2 ( 2 ,2 ,2 三氯乙氧 )甲酰胺基 α D 吡喃葡萄糖苷( 7) .在三甲基硅基三氟甲基磺酸酯 (TMSOTf)条件下 ,给体 5与受体 7反应得到一种新的二糖烯丙基 3 ,4,6 三 -氧 -乙酰 2 脱氧 2 ( 2 ,2 ,2 三氯乙氧 )甲酰胺基 β D 吡喃葡萄糖 ( 1→ 3 ) 4,6 氧 -亚苄基 2 脱氧 2 ( 2 ,2 ,2 三氯乙氧 )甲酰胺基 α D 吡喃葡萄糖糖苷 ( 10 ) ,收率为 3 9 2 % .当 7在无水BaO和Ba(OH) 2 ·8H2 O的条件下与BnBr进行 3 OH苄基化反应时 ,却得到了烯丙基 3 氧 -苄基 4,6 氧 -亚苄基 2 脱氧 2 羟甲酰胺基 α D 吡喃葡萄糖苷 ( 8) .改用Ag2 O条件下与BnBr进行苄基化 ,得到预期的烯丙基 3 氧 -苄基 4,6 氧 -亚苄基 2 脱氧 2 ( 2 ,2 ,2 三氯乙氧 )甲酰胺基 α D 吡喃葡萄糖苷 ( 9) ,从而避免了氨基保护基三氯乙氧甲酰基的水解 .标题化合物 10对枯草芽孢杆菌。

The donor, 3,4,6-tri-O-acetyl-2-deoxy-2-(2,2,2-trichloroethoxy)carbonylamino-alpha-D-glucopyranosyl trichloroacetimidate (5), and the acceptor, allyl 4, 6-O-benzylidene-2-deoxy-2-(2, 2, 2-trichloroethoxy)carbonylamino-alpha-D-glucopyranoside (7), were prepared from D-glucosamine hydrochloride. Trichloroethoxycarbonyl group was used as an amino protecting group and trichloroacetimidate was used as aleaving group. Reaction of 5 with glycosyl acceptor 7 in the presence of trimethylsilyl tiifluoromethanesulfonate afforded the fully protected disaccharide allyl 3,4,6-tri-O-acetyl-2-deoxy-2-(2,2,2-trichloroethoxy)carbonylamino-beta-D-glucopyranosyl-(1 --> 3)-4, 6-O-benzylidene-2-deoxy-2-(2,2,2-trichloroethoxy)carbonylamino-alpha-D-glucopyranoside (10) in yield of 39.2%. When 7 was treated with barium oxide, barium hydroxide octahydrate and benzyl bromide to realize benzylation at its 3-position, the unexpected product, allyl-3-O-benzyl-4,6-O-benzylidene-2-deoxy-2-hydroxy-carbonylamino-alpha-D-glucopyrunoside (8), was obtained. But allyl-3-O-benzyl-4,6-O-benzylidene-2-deoxy-2-(2,2,2-trieMoroethoxy)carbonylamino-alpha-D-glucopyranoside (9) was obtained smoothly without cleavage of the N-Troc in the benzylation of 3-hydroxyl group of 7 with BnBr in the presence of Ag2O. The title compound 10 has the moderate fungicidal activity to Bacillus subtilis and.. Rhizopus stolonifer et.