label: (5'R)-5'-isobutyl-5'-(methyl (4R)-2,3-O-isopropylidene-beta-L-erythrofuranosid-4-C-yl)-imidazolidin-2',4'-dione
label_lc: (5'r)-5'-isobutyl-5'-(methyl (4r)-2,3-o-isopropylidene-beta-l-erythrofuranosid-4-c-yl)-imidazolidin-2',4'-dione