以顺-1,3-二苄基-5-[(1S,2S)-(+)-苏式-1-羟甲基-2-(对硝基苯基)-2-羟乙基]-四氢-4H-吡咯并[3,4-d]咪唑-2,4,6-三酮为原料,经单乙酰化、NaBH4还原和酸水解得到标题化合物,与直接还原或是先经双乙酰化再还原的工艺相比,单乙酰化后再还原的选择性高达97.25%。并对单乙酰化物和双乙酰化物结构做了X单晶衍射测定,单乙酰化物的原子空间排布更利于选择性还原。 To a solution of cis-1,3-dibenzyl-5 - [(1S, 2S) - (+) - threo- 1 -hydroxymethyl-2- (p- nitrophenyl) -2-hydroxyethyl] Tetrahydro-4H-pyrrolo [3,4-d] imidazole-2,4,6-trione as starting material, monoacetylated, NaBH4 reduced and acid hydrolyzed to give the title compound either directly reduced or diacetyl Compared with the process of re-reduction, the selectivity of re-reduction after monoacetylation is as high as 97.25%. X-ray crystallography of monoacetylated and bisacetylated structures was also performed. The atomic arrangement of monoacetylated compounds was more conducive to selective reduction.