tert-butyl 3-[(2S)-2-amino-2-methylacetylamino]-1-azetidinecarboxylate 、 4-nitrobenzyl [(4-nitrobenzyloxy)carbonylimino-pyrazol-1-ylmethyl]carbamate 以
四氢呋喃 为溶剂,
以whereby 1.32 g of the title compound were obtained as an amorphous substance的产率得到tert-Butyl 3-[(2S)-2-[2,3-Di(4-nitrobenzyloxycarbonyl)guanidino]-2-methylacetylamino]-1-azetidinecarboxylate