(1R,2R,3S,4S,5R,6S) ethyl [6,7-dideoxy-6-{N3-benzyl-N1-(3,4-dimethoxyphenyl methyl)-(1-ureidyl)}-1,2:3,4-di-O-isopropylidene-tetrahydro-1,5-octopyranos-5-yl]-uronate 在
4 A molecular sieve 、
四丁基溴化铵 、
1,8-二氮杂双环[5.4.0]十一碳-7-烯 作用下,
以
甲苯 为溶剂,
反应 3.5h,
以95%的产率得到(1'R,2'R,3'S,4'S,5'R,6S) N
3-benzyl-N
1-(3,4-dimethoxyphenylmethyl)-5,6-dihydro-6-(1',2':3',4'-di-O-isopropylidene-1',2',3',4'-tetrahydro-1',5'-pyranos-5'-yl)-pyrimidin-2,4-dione