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