tert-butyl ((5S,8S,9S,Z)-12-((3aS,6R,6aR)-6-(3-((benzyloxy)methyl)-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-2-thioxodihydrofuro[3,4-d][1,3]dioxol-4(3aH)-ylidene)-5,7,8-trimethyl-3,6,10-trioxo-1-phenyl-2-oxa-4,7,11-triazadodecan-9-yl)carbamate