15-Methyl-(4S,13R,14R)-13,14-dihydroxy-4-isobutyl-3,6,9,12-tetraoxo-1-phenyl-2-oxa-5,8,11-triazapentadecane-15-carboxylate 、
(4R,5R,14S)-4,5-Bis(benzoyloxy)-14-isobutyl-3,6,9,12-tetraoxo-2-oxa-7,10,13-triazapentadecan-15-oic acid 在
4-二甲氨基吡啶 、
N,N'-二环己基碳二亚胺 作用下,
以
四氢呋喃 为溶剂,
以9.4%的产率得到3,16,20-Trimethyl-(3R,4R,13S,16R,17R,20S,29R,30R)-4,29-bis(benzoyloxy)-13,20-diisobutyl-17-[(9S)-9-isobutyl-4,7,10-trioxo-12-phenyl-11-oxa-2,5,8-triazadodec-1-anoyl]-1,5,8,11,14,19,22,25,28,32-decaoxo-1,32-diphenyl-2,15,18,31-tetraoxa-6,9,12,21,24,27...