Synthesis of screening substrates for the directed evolution of sialic acid aldolase: towards tailored enzymes for the preparation of influenza A sialidase inhibitor analogues
作者:Thomas Woodhall、Gavin Williams、Alan Berry、Adam Nelson
DOI:10.1039/b501503k
日期:——
The stereoselective synthesis of two epimeric screening substrates, (4R, 5R, 6R)- and (4S, 5R, 6R)-6-dipropylcarbamoyl-2-oxo-4,5,6-trihydroxy-hexanoic acid, for the directed evolution of sialic acid aldolase is described. The complementary methods relied on stereoselective indium-mediated additions of ethyl alpha-bromomethyl acrylate to functionalised aldehydes. With an alpha-hydroxy aldehyde, (2R
两种选择性异构筛选底物(4R,5R,6R)-和(4S,5R,6R)-6-二丙基氨基甲酰基-2-氧代-4,5,6-三羟基己酸的立体选择性合成描述了唾液酸醛缩酶。补充方法依赖于立体选择性铟介导的丙烯酸α-溴甲基丙烯酸乙酯向官能化醛的添加。用α-羟基醛,(2R,3R)-2,3-二羟基-4-氧代丁酸二丙酰胺进行螯合控制,合成产物(6R,5R,4S)-6-二丙基氨基甲酰基-2得到-亚甲基-4,5,6-三羟基己酸乙酯。相反,向(2R,3R)-N,N-二丙基-2,3-O-异亚丙基-4-氧代丁酰胺中添加立体化学结果与Felkin-Anh对照和抗加合物(4R,5R ,6R)-6-二丙基氨基甲酰基-2-亚甲基-4-羟基-5,主要产物6-O-异亚丙基-己酸乙酯。臭氧分解和脱保护以高收率得到了以呋喃糖和吡喃糖形式的混合物的筛选底物。