methyl 4-[(3aR,4R,6R,6aR)-6-({[bis(benzyloxy)phosphoryl]oxy}methyl)-2,2-dimethyltetrahydrofuro[3,4-d][1,3]dioxol-4-yl]-3-oxo-3,4-dihydro-2-pyrazinecarboxylate|Huagongshe