6-amino-2-({[(3a'R,4S,6'R,6a'R)-2,2,2',2'-tetramethyldihydro-3a'H-spiro[1,3-dioxolane-4,4'-furo[3,4-d][1,3]dioxol]-6'-yl]methyl}amino)-1,7-dihydro-8H-imidazo[4,5-g]quinazolin-8-one (non-preferred name)

P28720 — Queuine tRNA-ribosyltransferase