Improved synthesis and the crystal structure of methyl 4,6-dideoxy-4-(3-deoxy-l-glycero-tetronamido)-α-d-mannopyranoside, the methyl α-glycoside of the intracatenary repeating unit of the O-polysaccharide of Vibrio cholerae O:1
作者:Makoto Gotoh、Charles N. Barnes、Pavol Kováč
DOI:10.1016/0008-6215(94)84039-3
日期:1994.7
O-Deacetylation of 1 gave the title amide 2. Compound 2, obtained crystalline for the first time, was fully characterized, and its crystal structure was determined. Deoxytetronamido derivatives diastereomeric with 1 and 2, respectively, were obtained by the acylation of 12 with 2-O-acetyl-3-deoxy-D-glycero-tetronolactone (prepared from D-homoserine), and subsequent deacetylation. Structures of several byproducts
将可商购的L-高丝氨酸脱氨的粗产物乙酰化,并将形成的2-O-乙酰基-3-脱氧-L-甘油-四氢内酯(18)用于N-酰化过氧氨甲酰甲基(4-氨基-4甲基) ,6-二脱氧-α-D-甘露吡喃糖苷,12)及其2,3-O-异亚丙基衍生物。从反应中分离出的主要产物是结晶的甲基4-(4-O-乙酰基-3-脱氧-L-甘油-四氢酰胺基)-4,6-二脱氧-α-D-+ ++甘露吡喃糖苷(1,70- 75%)是由最初形成的2'-O-乙酰基衍生物中的乙酰基迁移引起的。1的O-脱乙酰基化得到标题酰胺2。对首次获得结晶的化合物2进行了充分表征,并确定了其晶体结构。Deoxytetronamido衍生物分别为1和2的非对映异构体,通过用2-O-乙酰基-3-脱氧-D-甘油-四氢内酯(由D-高丝氨酸制备)对12进行酰化,然后进行脱乙酰基而获得。由它们的光谱特征推导了12与18反应的几种副产物的结构。由于这些副产物是2的各种O-乙