1-(3-cyano-5-(ethoxycarbonyl)-6-ethylpyridin-2-yl)azetidine-3-carboxylic acid 、
1-(2,4-difluorphenyl)methanesulfonamide 以to give ethyl 5-cyano-6-(3-{[(2,4-difluorobenzyl)sulfonyl]carbamoyl}azetidin-1-yl)-2-ethylnicotinate的产率得到ethyl 5-cyano-6-(3-{[(2,4-difluorobenzyl)sulfonyl]carbamoyl}azetidin-1-yl)-2-ethylnicotinate