作者:Ivan Hemeon、Andrew J. Bennet
DOI:10.1039/b605218e
日期:——
alpha-(bromomethyl)acrylate. Following ozonolysis of the corresponding tert-butyl enoate esters and diastereomer separation, the tert-butyl ester of 4-nitrosialic acid (11b) could be deprotected under acidic conditions to afford . The target compound is a useful intermediate for synthesis of a variety of C-4 substituted sialic acid derivatives, and it is synthesised by a modular route.
从开始的七个步骤中完成了4-deoxy-4-nitrosialic acid(3,4,5-trideoxy-4-nitro-D-glycero-beta-D-galacto-non-2-ulyryranosonic acid,5)的合成。来自D-阿拉伯糖。6碳片段2-乙酰氨基-1,2-二脱氧-1-硝基-D-甘露醇(6)与α-(溴甲基)丙烯酸乙酯的偶联得到5-乙酰氨基-2的2:1混合物, 3,4,5-四脱氧-2-亚甲基-4-硝基-D-甘油-D-半乳糖壬酸酯(9a-S)和乙基5-乙酰氨基-2,3,4,5-四脱氧-2-亚甲基- 4-硝基-D-甘油-D-talo-壬酸酯(9a-R)。对该烯酮的混合物进行臭氧分解,并在还原该臭氧化物后,将所得产物环化成吡喃糖苷。通过分步结晶分离目标化合物4-脱氧-4-硝基唾液酸乙酯(11a)。乙酯的水解被证明是有问题的。因此,通过使用α-(溴甲基)丙烯酸叔丁酯对合成