tert-Butyl 14-(N-Boc-amino)-1-{3-[1,3-bis(1',6'-anhydro-2',3'-isopropylidine)-beta- -D-manopyrano-4-yloxy]propan-2-ylcarbamoyl}phenoxy-13,15-dioxo-3,6,9-trioxa- 12,16-diazanonadecan-19-oate