Daunorubicin 45mg/m^2/day (days 1-2) Cytarabine 100mg/m^2/day (continuous infusion on days 1-5) Selinexor same dose as induction (days 1,3,8,10) unless dose limiting toxicity (DLT) dictates a dose reduction. Selinexor will be given 2 hours prior to daunorubicin on day 1.