The present invention concerns a novel enantiomer of 9-(3-fluorophenyl)-5-(2- hydroxyethyl)-6,9-dihydro-[l,3]dioxolo[4,5-g]furo[3,4-b]quinolin-8(5H)-one (SU056), as well as pharmaceutically acceptable salts thereof, pharmaceutical compositions comprising it, and its uses in medical treatments, particularly including cancer treatments.