(S)-tert-butyl-4-((18-((4R,5S)-5-((R)-6-(benzyloxy)-1-(methoxymethoxy)hexyl)-2,2-dimethyl-1,3-dioxolan-4-yl)-16-oxooctadec-17-ynyloxy)methyl)-2,2-dimethyloxazolidine-3-carboxylate