2-((S)-1-{[2-((S)-1-{[2-((S)-1-Amino-2-tert-butoxycarbonylamino-ethyl)-oxazole-4-carbonyl]-amino}-2-tert-butoxycarbonylamino-ethyl)-oxazole-4-carbonyl]-amino}-2-tert-butoxycarbonylamino-ethyl)-oxazole-4-carboxylic acid 在
N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以14%的产率得到tri-tert-butyl (((12Z,52Z,92Z,2S,6S,10S)-4,8,12-trioxo-3,7,11-triaza-1(2,4),5,9(4,2)-trioxazolacyclododecaphane-2,6,10-triyl)tris(methylene))tricarbamate