(3R,3aS)-3-((t-butyldimethylsiloxy)methyl)-1-oxo-1,3,3a,4-tetrahydrobenzo[b]oxazolo[3,4-d][1,4]oxazin-7-carbonitrile 、
四丁基氟化铵 以afforded 0.24 g white solid, yield 65.3%的产率得到(3R,3aS)-3-(hydroxymethyl)-1-oxo-1,3,3a,4-tetrahydrobenzo[b]oxazolo[3,4-d][1,4]oxazin-7-carbonitrile