4-sec-butyl-2-(2,3-difluorobenzylsulfanyl)-6-hydroxy-pyrimidine-5-carbonitrile 生成 4-((R)-sec-butyl)-2-(2,3-difluorobenzylsulfanyl)-6-hydroxypyrimidine-5-carbonitrile 、 4-((S)-sec-butyl)-2-(2,3-difluorobenzylsulfanyl)-6-hydroxypyrimidine-5-carbonitrile