(+/-)-1-苄氧羰基-4-Boc-哌嗪-2-羧酸甲酯 、 3-溴-2-甲基丙烯 以the title compound (1.80 g, yield 40%) was obtained as an oil by an operation similar to that of Reference Example 1的产率得到2-methyl 4-tert-butyl 1-benzyl 2-(2-methylprop-2-en-1-yl)piperazine-1,2,4-tricarboxylate