Azetidine compounds of the general formula I
wherein Ar represents an aryl group and X represents a hydrogen atom, a carboxyl group or a hydroxymethyl group; their preparation from pentaerythritol via compounds of formula
wherein Hal represents chlorine, bromine or iodine, Y represents oxygen or
and Z represents Hal or OH, together with their use as intermediates in the preparation of 3-carboxyazetidine; also the compounds of formula
                            通式 I 的氮杂
环丁烷化合物 其中 Ar 代表芳基,X 代表氢原子、羧基或羟甲基;通过式中 Hal 代表
氯、
溴或
碘,Y 代表氧或,Z 代表 Hal 或 OH 的化合物从
季戊四醇制备氮杂
环丁烷,以及将其用作制备 3-羧基氮杂
环丁烷的中间体;还有式中化合物